Preeclampsia

Complex MONDO:0005081 Pathograph 3 Hypertensive disorder of pregnancy Placental disease

Preeclampsia is a multisystemic pregnancy disorder characterized by new-onset hypertension and often proteinuria after 20 weeks of gestation, which can progress to multi-organ dysfunction including hepatic, renal, and cerebral disease. It complicates 2-8% of pregnancies globally and is a leading cause of maternal and perinatal morbidity and mortality. The pathophysiology involves defective trophoblast invasion and spiral artery remodeling leading to placental ischemia, followed by release of anti-angiogenic factors (sFlt-1, soluble endoglin) that cause widespread maternal endothelial dysfunction. The only definitive treatment is delivery of the fetus and placenta.

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3
Pathophys.
10
Phenotypes
3
Pathograph
4
Genes
5
Treatments
3
Subtypes
1
Deep Research
◆

Subtypes

3
Early-onset preeclampsia (<34 weeks)
Preeclampsia with onset before 34 weeks of gestation. Strongly associated with defective placentation and more severe angiogenic imbalance. Associated with higher rates of maternal and fetal complications, intrauterine growth restriction, and features resembling atherosclerosis.
Show evidence (1 reference)
PMID:35177220 SUPPORT Human Clinical
"Early-onset preeclampsia has many features in common with atherosclerosis, whereas late-onset preeclampsia seems to result from a mismatch of fetal demands and maternal supply, that is, a metabolic crisis."
Distinguishes early-onset preeclampsia as having features of vascular pathology resembling atherosclerosis.
Late-onset preeclampsia (>=34 weeks)
Preeclampsia with onset at or after 34 weeks of gestation. The more common form, often associated with less severe placental pathology and thought to result from a mismatch between fetal metabolic demands and maternal cardiovascular supply capacity.
Show evidence (1 reference)
PMID:35177220 SUPPORT Human Clinical
"Early-onset preeclampsia has many features in common with atherosclerosis, whereas late-onset preeclampsia seems to result from a mismatch of fetal demands and maternal supply, that is, a metabolic crisis."
Characterizes late-onset preeclampsia as a metabolic crisis from demand-supply mismatch.
HELLP syndrome
Severe variant characterized by hemolysis, elevated liver enzymes, and low platelet count. Represents the severe end of the preeclampsia spectrum and can occur with or without significant hypertension or proteinuria.
Show evidence (1 reference)
PMID:34033373 SUPPORT Human Clinical
"This disease represents a spectrum of hypertensive disease in pregnancy, beginning with gestational hypertension and progressing to develop severe features, ultimately leading to its more severe manifestations, such as eclampsia and HELLP syndrome."
Identifies HELLP syndrome as a severe manifestation on the preeclampsia spectrum.
⚙

Pathophysiology

3
Defective Trophoblast Invasion and Spiral Artery Remodeling
In normal pregnancy, extravillous trophoblasts invade the uterine decidua and remodel maternal spiral arteries into high-capacitance, low-resistance vessels. In preeclampsia, this invasion is shallow and incomplete, resulting in narrow, high-resistance spiral arteries that fail to adequately perfuse the placenta. The resulting placental ischemia and hypoxia trigger downstream pathological cascades.
extravillous trophoblast link decidual natural killer cell link
placenta development link ↓ DECREASED vasculogenesis link ↓ DECREASED
Downstream
Placental Anti-Angiogenic Factor Release Placental ischemia from poor spiral artery remodeling triggers release of anti-angiogenic factors into the maternal circulation.
Show evidence (2 references)
PMID:39062815 SUPPORT Human Clinical
"PE is initiated by poor placentation due to inadequate trophoblast invasion and improper spiral artery remodeling, leading to placental hypoxia."
Directly describes the defective trophoblast invasion and spiral artery remodeling as the initiating event in preeclampsia.
PMID:35177220 SUPPORT Human Clinical
"a growing body of evidence suggests that products of an ischemic or a stressed placenta are responsible for the vascular changes that characterize this syndrome."
Supports the concept that placental ischemia (from defective remodeling) drives vascular pathology.
Placental Anti-Angiogenic Factor Release
The ischemic placenta releases excess anti-angiogenic factors, primarily soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sEng), into the maternal circulation. sFlt-1 acts as a decoy receptor that sequesters VEGF and PlGF, while sEng inhibits TGF-beta signaling. Together, these factors create a systemic anti-angiogenic state that disrupts normal endothelial function. Levels of sFlt-1 rise and PlGF fall weeks before clinical onset.
syncytiotrophoblast link
VEGF receptor signaling pathway link ↓ DECREASED angiogenesis link ↓ DECREASED response to hypoxia link
Downstream
Maternal Endothelial Dysfunction Anti-angiogenic factors in the maternal circulation cause widespread endothelial injury and dysfunction.
Show evidence (6 references)
PMID:12618519 SUPPORT Human Clinical
"we confirm that placental soluble fms-like tyrosine kinase 1 (sFlt1), an antagonist of VEGF and placental growth factor (PlGF), is upregulated in preeclampsia, leading to increased systemic levels of sFlt1 that fall after delivery."
Landmark paper demonstrating that placental sFlt-1 is upregulated in preeclampsia with systemic elevation.
PMID:14764923 SUPPORT Human Clinical
"The sFlt-1 level increased beginning approximately five weeks before the onset of preeclampsia."
Shows that sFlt-1 rises weeks before clinical disease, consistent with placental release preceding symptoms.
PMID:14764923 SUPPORT Human Clinical
"Increased levels of sFlt-1 and reduced levels of PlGF predict the subsequent development of preeclampsia."
Confirms the predictive anti-angiogenic imbalance pattern.
+ 3 more references
Maternal Endothelial Dysfunction
The anti-angiogenic imbalance causes widespread maternal endothelial dysfunction, manifesting as vasoconstriction, increased vascular permeability, and activation of the coagulation cascade. This leads to the clinical features of hypertension, proteinuria (from glomerular endotheliosis), hepatic dysfunction, cerebral edema, and thrombocytopenia. The characteristic renal lesion is glomerular endotheliosis.
blood vessel endothelial cell link platelet link
innate immune response link inflammatory response link
Show evidence (3 references)
PMID:12618519 SUPPORT Model Organism
"administration of sFlt1 to pregnant rats induces hypertension, proteinuria, and glomerular endotheliosis, the classic lesion of preeclampsia."
Direct demonstration that sFlt-1 causes the clinical triad of hypertension, proteinuria, and glomerular endotheliosis.
PMID:30792480 SUPPORT Human Clinical
"Maternal endothelial dysfunction due to circulating factors of fetal origin from the placenta is a hallmark of pre-eclampsia."
Identifies endothelial dysfunction from placental factors as the hallmark of preeclampsia.
PMID:16751767 SUPPORT In Vitro
"sEng impairs binding of TGF-beta1 to its receptors and downstream signaling including effects on activation of eNOS and vasodilation, suggesting that sEng leads to dysregulated TGF-beta signaling in the vasculature."
Biochemical/cell-based evidence that sEng disrupts TGF-beta receptor binding and eNOS activation.
⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for Preeclampsia Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.
●

Phenotypes

10
Blood 2
Thrombocytopenia Thrombocytopenia (HP:0001873)
Show evidence (1 reference)
PMID:16751767 SUPPORT Model Organism
"leading to severe preeclampsia including the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome"
Low platelets are a defining component of HELLP syndrome within the preeclampsia spectrum.
Hemolytic anemia Hemolytic anemia (HP:0001878)
Show evidence (1 reference)
PMID:16751767 SUPPORT Model Organism
"leading to severe preeclampsia including the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome"
Hemolysis is a defining component of HELLP syndrome.
Cardiovascular 1
Hypertension VERY_FREQUENT Hypertension (HP:0000822)
Show evidence (2 references)
PMID:34033373 SUPPORT Human Clinical
"The parameters for initial identification of hypertension in the context of pregnancy-induced hypertension constituting the "mild range" are specifically defined as a systolic blood pressure (SBP) of 140 mm Hg or more or diastolic blood pressure (DBP) of 90 mm Hg or more on 2 occasions at least..."
Defines the diagnostic blood pressure criteria for preeclampsia.
PMID:32443079 SUPPORT Human Clinical
"Hypertensive disorders of pregnancy constitute one of the leading causes of maternal and perinatal mortality worldwide."
Establishes hypertensive disorders as a defining feature of the preeclampsia spectrum.
Eye 1
Visual disturbances Blurred vision (HP:0000622)
Show evidence (1 reference)
PMID:39247143 SUPPORT Human Clinical
"Severe preeclampsia is defined as blood pressure (BP) >160/110 mmHg with warning signs such as headache, blurring of vision, and epigastric pain."
Explicitly identifies blurring of vision as a warning sign of severe preeclampsia.
Genitourinary 1
Proteinuria Proteinuria (HP:0000093)
Show evidence (1 reference)
PMID:30792480 SUPPORT Human Clinical
"The disease presents with new-onset hypertension and often proteinuria in the mother, which can progress to multi-organ dysfunction, including hepatic, renal and cerebral disease, if the fetus and placenta are not delivered."
Identifies proteinuria as a frequent but not universal feature of preeclampsia.
Metabolism 2
Elevated hepatic transaminases Elevated circulating hepatic transaminase concentration (HP:0002910)
Show evidence (1 reference)
PMID:16751767 SUPPORT Model Organism
"leading to severe preeclampsia including the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome"
Elevated liver enzymes are a defining feature of HELLP syndrome.
Pulmonary edema Pulmonary edema (HP:0100598)
Pulmonary edema is a recognized severe complication of preeclampsia, resulting from endothelial dysfunction, decreased oncotic pressure, and iatrogenic fluid overload. It is included in ACOG criteria for severe features of preeclampsia.
Nervous System 2
Seizures (eclampsia) Seizure (HP:0001250)
Show evidence (1 reference)
PMID:35177220 SUPPORT Human Clinical
"once thought to be a disease of the central nervous system, recognized by the occurrence of seizures (ie, eclampsia)"
Eclamptic seizures are the historically defining severe complication of preeclampsia.
Headache Headache (HP:0002315)
Show evidence (1 reference)
PMID:39247143 SUPPORT Human Clinical
"Severe preeclampsia is defined as blood pressure (BP) >160/110 mmHg with warning signs such as headache, blurring of vision, and epigastric pain."
Explicitly identifies headache as a warning sign of severe preeclampsia.
Growth 1
Intrauterine growth retardation Intrauterine growth retardation (HP:0001511)
Show evidence (1 reference)
PMID:14764923 SUPPORT Human Clinical
"Alterations in the levels of sFlt-1 and free PlGF were greater in women with an earlier onset of preeclampsia and in women in whom preeclampsia was associated with a small-for-gestational-age infant."
Links angiogenic factor alterations to small-for-gestational-age infants in preeclampsia.
🧬

Genetic Associations

4
FLT1 (Risk Factor)
Show evidence (2 references)
PMID:39062815 SUPPORT Human Clinical
"Genetic and epigenetic modifications, including polymorphisms in the Fms-like tyrosine kinase 1 (FLT1) gene and altered microRNA (miRNA) expression, play critical roles."
Identifies FLT1 polymorphisms as playing a critical role in preeclampsia.
PMID:12618519 SUPPORT Human Clinical
"we confirm that placental soluble fms-like tyrosine kinase 1 (sFlt1), an antagonist of VEGF and placental growth factor (PlGF), is upregulated in preeclampsia"
Demonstrates sFlt-1 (FLT1 gene product) upregulation in preeclamptic placentas.
PGF (Risk Factor)
Show evidence (1 reference)
PMID:14764923 SUPPORT Human Clinical
"Increased levels of sFlt-1 and reduced levels of PlGF predict the subsequent development of preeclampsia."
PlGF reduction is a key predictive feature of preeclampsia.
ENG (Risk Factor)
Show evidence (1 reference)
PMID:16751767 SUPPORT Model Organism
"Our results suggest that sEng may act in concert with sFlt1 to induce severe preeclampsia."
Demonstrates the pathogenic role of soluble endoglin (ENG gene product) in severe preeclampsia.
VEGFA (Risk Factor)
Show evidence (2 references)
PMID:12618519 SUPPORT Human Clinical
"increased circulating sFlt1 in patients with preeclampsia is associated with decreased circulating levels of free VEGF and PlGF"
Human clinical data showing that sFlt-1 excess sequesters free VEGF in preeclampsia patients.
PMID:12618519 SUPPORT In Vitro
"resulting in endothelial dysfunction in vitro that can be rescued by exogenous VEGF and PlGF."
In vitro evidence that exogenous VEGF can rescue sFlt-1-induced endothelial dysfunction.
💊

Treatments

5
Delivery
Action: labor induction MAXO:0000861
Delivery of the fetus and placenta is the only definitive treatment for preeclampsia. Timing depends on gestational age and severity, balancing maternal risk against fetal prematurity. Generally recommended at 37 weeks for preeclampsia without severe features, and earlier if severe features or maternal/fetal deterioration occurs.
Show evidence (1 reference)
PMID:30792480 SUPPORT Human Clinical
"which can progress to multi-organ dysfunction, including hepatic, renal and cerebral disease, if the fetus and placenta are not delivered."
Identifies delivery as the necessary intervention to prevent progression.
Low-dose aspirin prophylaxis
Action: Pharmacotherapy NCIT:C15986
Agent: acetylsalicylic acid ↗
Low-dose aspirin (150 mg daily) initiated at 11-14 weeks of gestation in women identified as high risk reduces the incidence of preterm preeclampsia by approximately 62%. This is a preventive intervention, not a treatment for established disease.
Show evidence (1 reference)
PMID:28657417 SUPPORT Human Clinical
"Preterm preeclampsia occurred in 13 participants (1.6%) in the aspirin group, as compared with 35 (4.3%) in the placebo group (odds ratio in the aspirin group, 0.38; 95% confidence interval, 0.20 to 0.74; P=0.004)."
The ASPRE trial demonstrated a 62% reduction in preterm preeclampsia with aspirin 150 mg daily.
Magnesium sulfate for seizure prevention
Action: Pharmacotherapy NCIT:C15986
Agent: magnesium sulfate ↗
Magnesium sulfate is the first-line agent for prevention and treatment of eclamptic seizures. It halves the risk of eclampsia in women with preeclampsia and probably reduces maternal mortality.
Show evidence (1 reference)
PMID:12057549 SUPPORT Human Clinical
"Women allocated magnesium sulphate had a 58% lower risk of eclampsia (95% CI 40-71) than those allocated placebo (40, 0.8%, vs 96, 1.9%; 11 fewer women with eclampsia per 1000 women)."
The Magpie trial demonstrated that magnesium sulfate halves eclampsia risk.
Antihypertensive therapy (labetalol)
Action: Pharmacotherapy NCIT:C15986
Agent: labetalol ↗
Labetalol is a first-line antihypertensive for acute blood pressure management in severe preeclampsia, used to prevent hypertensive emergencies and stroke.
Show evidence (1 reference)
PMID:39247143 SUPPORT Human Clinical
"Nifedipine (C17H18N2O6), labetalol (C19H24N2O3), and hydralazine (C8H8N4) are commonly used drugs, and all are recommended as first-line agents."
Identifies labetalol as a recommended first-line agent for acute hypertensive management in pregnancy.
Antihypertensive therapy (nifedipine)
Action: Pharmacotherapy NCIT:C15986
Agent: nifedipine ↗
Nifedipine is an alternative first-line oral antihypertensive for acute severe hypertension in preeclampsia.
Show evidence (1 reference)
PMID:39247143 SUPPORT Human Clinical
"oral nifedipine has been proposed as a first-line alternative to intravenous labetalol."
Identifies nifedipine as a first-line alternative antihypertensive for severe preeclampsia.
🔬

Biochemical Markers

3
Elevated sFlt-1 (Elevated)
Context: diagnostic biomarker
Show evidence (1 reference)
PMID:14764923 SUPPORT Human Clinical
"At the onset of clinical disease, the mean serum level in the women with preeclampsia was 4382 pg per milliliter, as compared with 1643 pg per milliliter in controls with fetuses of similar gestational age (P<0.001)."
Quantifies the elevation of sFlt-1 in preeclampsia versus controls.
Decreased PlGF (Decreased)
Context: diagnostic biomarker
Show evidence (1 reference)
PMID:14764923 SUPPORT Human Clinical
"The PlGF levels were significantly lower in the women who later had preeclampsia than in the controls beginning at 13 to 16 weeks of gestation (mean, 90 pg per milliliter vs. 142 pg per milliliter, P=0.01)"
Shows that PlGF depression begins early in the second trimester before clinical disease.
Elevated soluble endoglin (Elevated)
Context: diagnostic biomarker
Show evidence (1 reference)
PMID:16751767 SUPPORT Human Clinical
"We report a novel placenta-derived soluble TGF-beta coreceptor, endoglin (sEng), which is elevated in the sera of preeclamptic individuals, correlates with disease severity and falls after delivery."
Identifies elevated sEng as correlating with disease severity.
{ }

Source YAML

click to show 
name: Preeclampsia
creation_date: "2026-05-13T00:00:00Z"
updated_date: "2026-05-13T18:00:00Z"
category: Complex
synonyms:
- Pre-eclampsia
- Toxemia of pregnancy
- Pregnancy-induced hypertension with proteinuria
description: >
  Preeclampsia is a multisystemic pregnancy disorder characterized by new-onset
  hypertension and often proteinuria after 20 weeks of gestation, which can
  progress to multi-organ dysfunction including hepatic, renal, and cerebral
  disease. It complicates 2-8% of pregnancies globally and is a leading cause
  of maternal and perinatal morbidity and mortality. The pathophysiology involves
  defective trophoblast invasion and spiral artery remodeling leading to placental
  ischemia, followed by release of anti-angiogenic factors (sFlt-1, soluble
  endoglin) that cause widespread maternal endothelial dysfunction. The only
  definitive treatment is delivery of the fetus and placenta.
disease_term:
  preferred_term: preeclampsia
  term:
    id: MONDO:0005081
    label: preeclampsia
parents:
- Hypertensive disorder of pregnancy
- Placental disease
has_subtypes:
- name: Early-onset
  display_name: Early-onset preeclampsia (<34 weeks)
  description: >
    Preeclampsia with onset before 34 weeks of gestation. Strongly associated
    with defective placentation and more severe angiogenic imbalance. Associated
    with higher rates of maternal and fetal complications, intrauterine growth
    restriction, and features resembling atherosclerosis.
  evidence:
  - reference: PMID:35177220
    reference_title: "Preeclampsia and eclampsia: the conceptual evolution of a syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Early-onset preeclampsia has many features in common with atherosclerosis, whereas late-onset preeclampsia seems to result from a mismatch of fetal demands and maternal supply, that is, a metabolic crisis."
    explanation: Distinguishes early-onset preeclampsia as having features of vascular pathology resembling atherosclerosis.
- name: Late-onset
  display_name: Late-onset preeclampsia (>=34 weeks)
  description: >
    Preeclampsia with onset at or after 34 weeks of gestation. The more common
    form, often associated with less severe placental pathology and thought to
    result from a mismatch between fetal metabolic demands and maternal
    cardiovascular supply capacity.
  evidence:
  - reference: PMID:35177220
    reference_title: "Preeclampsia and eclampsia: the conceptual evolution of a syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Early-onset preeclampsia has many features in common with atherosclerosis, whereas late-onset preeclampsia seems to result from a mismatch of fetal demands and maternal supply, that is, a metabolic crisis."
    explanation: Characterizes late-onset preeclampsia as a metabolic crisis from demand-supply mismatch.
- name: HELLP
  display_name: HELLP syndrome
  description: >
    Severe variant characterized by hemolysis, elevated liver enzymes, and low
    platelet count. Represents the severe end of the preeclampsia spectrum and
    can occur with or without significant hypertension or proteinuria.
  evidence:
  - reference: PMID:34033373
    reference_title: "Preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "This disease represents a spectrum of hypertensive disease in pregnancy, beginning with gestational hypertension and progressing to develop severe features, ultimately leading to its more severe manifestations, such as eclampsia and HELLP syndrome."
    explanation: Identifies HELLP syndrome as a severe manifestation on the preeclampsia spectrum.
pathophysiology:
- name: Defective Trophoblast Invasion and Spiral Artery Remodeling
  description: >
    In normal pregnancy, extravillous trophoblasts invade the uterine decidua
    and remodel maternal spiral arteries into high-capacitance, low-resistance
    vessels. In preeclampsia, this invasion is shallow and incomplete, resulting
    in narrow, high-resistance spiral arteries that fail to adequately perfuse
    the placenta. The resulting placental ischemia and hypoxia trigger downstream
    pathological cascades.
  cell_types:
  - preferred_term: extravillous trophoblast
    term:
      id: CL:0008036
      label: extravillous trophoblast
  - preferred_term: decidual natural killer cell
    term:
      id: CL:0002343
      label: decidual natural killer cell, human
  biological_processes:
  - preferred_term: placenta development
    term:
      id: GO:0001890
      label: placenta development
    modifier: DECREASED
  - preferred_term: vasculogenesis
    term:
      id: GO:0001570
      label: vasculogenesis
    modifier: DECREASED
  downstream:
  - target: Placental Anti-Angiogenic Factor Release
    description: Placental ischemia from poor spiral artery remodeling triggers release of anti-angiogenic factors into the maternal circulation.
    evidence:
    - reference: PMID:39062815
      reference_title: "A Narrative Review on the Pathophysiology of Preeclampsia."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "PE is initiated by poor placentation due to inadequate trophoblast invasion and improper spiral artery remodeling, leading to placental hypoxia. This triggers the release of anti-angiogenic factors such as soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng), causing widespread endothelial dysfunction and systemic inflammation."
      explanation: Directly describes the causal chain from defective trophoblast invasion through placental hypoxia to anti-angiogenic factor release.
  evidence:
  - reference: PMID:39062815
    reference_title: "A Narrative Review on the Pathophysiology of Preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "PE is initiated by poor placentation due to inadequate trophoblast invasion and improper spiral artery remodeling, leading to placental hypoxia."
    explanation: Directly describes the defective trophoblast invasion and spiral artery remodeling as the initiating event in preeclampsia.
  - reference: PMID:35177220
    reference_title: "Preeclampsia and eclampsia: the conceptual evolution of a syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "a growing body of evidence suggests that products of an ischemic or a stressed placenta are responsible for the vascular changes that characterize this syndrome."
    explanation: Supports the concept that placental ischemia (from defective remodeling) drives vascular pathology.
- name: Placental Anti-Angiogenic Factor Release
  description: >
    The ischemic placenta releases excess anti-angiogenic factors, primarily
    soluble fms-like tyrosine kinase 1 (sFlt-1) and soluble endoglin (sEng),
    into the maternal circulation. sFlt-1 acts as a decoy receptor that
    sequesters VEGF and PlGF, while sEng inhibits TGF-beta signaling. Together,
    these factors create a systemic anti-angiogenic state that disrupts normal
    endothelial function. Levels of sFlt-1 rise and PlGF fall weeks before
    clinical onset.
  cell_types:
  - preferred_term: syncytiotrophoblast
    term:
      id: CL:0000525
      label: syncytiotrophoblast cell
  biological_processes:
  - preferred_term: VEGF receptor signaling pathway
    term:
      id: GO:0048010
      label: vascular endothelial growth factor receptor signaling pathway
    modifier: DECREASED
  - preferred_term: angiogenesis
    term:
      id: GO:0001525
      label: angiogenesis
    modifier: DECREASED
  - preferred_term: response to hypoxia
    term:
      id: GO:0001666
      label: response to hypoxia
  downstream:
  - target: Maternal Endothelial Dysfunction
    description: Anti-angiogenic factors in the maternal circulation cause widespread endothelial injury and dysfunction.
    evidence:
    - reference: PMID:12618519
      reference_title: "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "increased circulating sFlt1 in patients with preeclampsia is associated with decreased circulating levels of free VEGF and PlGF"
      explanation: Human clinical observation showing sFlt-1 elevation associates with decreased free VEGF and PlGF.
    - reference: PMID:12618519
      reference_title: "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia."
      supports: SUPPORT
      evidence_source: IN_VITRO
      snippet: "resulting in endothelial dysfunction in vitro that can be rescued by exogenous VEGF and PlGF."
      explanation: In vitro demonstration that endothelial dysfunction from sFlt-1 excess is reversible with VEGF/PlGF.
  evidence:
  - reference: PMID:12618519
    reference_title: "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "we confirm that placental soluble fms-like tyrosine kinase 1 (sFlt1), an antagonist of VEGF and placental growth factor (PlGF), is upregulated in preeclampsia, leading to increased systemic levels of sFlt1 that fall after delivery."
    explanation: Landmark paper demonstrating that placental sFlt-1 is upregulated in preeclampsia with systemic elevation.
  - reference: PMID:14764923
    reference_title: "Circulating angiogenic factors and the risk of preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The sFlt-1 level increased beginning approximately five weeks before the onset of preeclampsia."
    explanation: Shows that sFlt-1 rises weeks before clinical disease, consistent with placental release preceding symptoms.
  - reference: PMID:14764923
    reference_title: "Circulating angiogenic factors and the risk of preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Increased levels of sFlt-1 and reduced levels of PlGF predict the subsequent development of preeclampsia."
    explanation: Confirms the predictive anti-angiogenic imbalance pattern.
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "sEng inhibits formation of capillary tubes in vitro"
    explanation: In vitro evidence that soluble endoglin has anti-angiogenic effects.
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Its effects in pregnant rats are amplified by coadministration of sFlt1, leading to severe preeclampsia including the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome and restriction of fetal growth."
    explanation: Rat model demonstrates that sEng synergizes with sFlt-1 to produce severe preeclampsia including HELLP syndrome.
  - reference: PMID:39062815
    reference_title: "A Narrative Review on the Pathophysiology of Preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "This triggers the release of anti-angiogenic factors such as soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng), causing widespread endothelial dysfunction and systemic inflammation."
    explanation: Summarizes the anti-angiogenic cascade from placental hypoxia to endothelial dysfunction.
- name: Maternal Endothelial Dysfunction
  description: >
    The anti-angiogenic imbalance causes widespread maternal endothelial
    dysfunction, manifesting as vasoconstriction, increased vascular
    permeability, and activation of the coagulation cascade. This leads to
    the clinical features of hypertension, proteinuria (from glomerular
    endotheliosis), hepatic dysfunction, cerebral edema, and
    thrombocytopenia. The characteristic renal lesion is glomerular
    endotheliosis.
  cell_types:
  - preferred_term: blood vessel endothelial cell
    term:
      id: CL:0000071
      label: blood vessel endothelial cell
  - preferred_term: platelet
    term:
      id: CL:0000233
      label: platelet
  biological_processes:
  - preferred_term: innate immune response
    term:
      id: GO:0045087
      label: innate immune response
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
  evidence:
  - reference: PMID:12618519
    reference_title: "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "administration of sFlt1 to pregnant rats induces hypertension, proteinuria, and glomerular endotheliosis, the classic lesion of preeclampsia."
    explanation: Direct demonstration that sFlt-1 causes the clinical triad of hypertension, proteinuria, and glomerular endotheliosis.
  - reference: PMID:30792480
    reference_title: "Pre-eclampsia: pathogenesis, novel diagnostics and therapies."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Maternal endothelial dysfunction due to circulating factors of fetal origin from the placenta is a hallmark of pre-eclampsia."
    explanation: Identifies endothelial dysfunction from placental factors as the hallmark of preeclampsia.
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "sEng impairs binding of TGF-beta1 to its receptors and downstream signaling including effects on activation of eNOS and vasodilation, suggesting that sEng leads to dysregulated TGF-beta signaling in the vasculature."
    explanation: Biochemical/cell-based evidence that sEng disrupts TGF-beta receptor binding and eNOS activation.
phenotypes:
- name: Hypertension
  category: Clinical
  description: >
    New-onset hypertension after 20 weeks of gestation, defined as systolic
    blood pressure >=140 mmHg or diastolic >=90 mmHg on two occasions at
    least 4 hours apart. Severe-range hypertension is >=160/110 mmHg.
  frequency: VERY_FREQUENT
  phenotype_term:
    preferred_term: Maternal hypertension
    term:
      id: HP:0000822
      label: Hypertension
  evidence:
  - reference: PMID:34033373
    reference_title: "Preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The parameters for initial identification of hypertension in the context of pregnancy-induced hypertension constituting the \"mild range\" are specifically defined as a systolic blood pressure (SBP) of 140 mm Hg or more or diastolic blood pressure (DBP) of 90 mm Hg or more on 2 occasions at least 4 hours apart"
    explanation: Defines the diagnostic blood pressure criteria for preeclampsia.
  - reference: PMID:32443079
    reference_title: "Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin, Number 222."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Hypertensive disorders of pregnancy constitute one of the leading causes of maternal and perinatal mortality worldwide."
    explanation: Establishes hypertensive disorders as a defining feature of the preeclampsia spectrum.
- name: Proteinuria
  category: Clinical
  description: >
    New-onset proteinuria, typically >=300 mg per 24-hour urine collection or
    protein/creatinine ratio >=0.3 mg/dL. While historically required for
    diagnosis, current guidelines recognize preeclampsia can occur without
    proteinuria if other signs of end-organ dysfunction are present.
  phenotype_term:
    preferred_term: Proteinuria
    term:
      id: HP:0000093
      label: Proteinuria
  evidence:
  - reference: PMID:30792480
    reference_title: "Pre-eclampsia: pathogenesis, novel diagnostics and therapies."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The disease presents with new-onset hypertension and often proteinuria in the mother, which can progress to multi-organ dysfunction, including hepatic, renal and cerebral disease, if the fetus and placenta are not delivered."
    explanation: Identifies proteinuria as a frequent but not universal feature of preeclampsia.
- name: Thrombocytopenia
  category: Clinical
  description: >
    Low platelet count, particularly prominent in HELLP syndrome. Reflects
    endothelial activation and consumptive coagulopathy.
  phenotype_term:
    preferred_term: Thrombocytopenia
    term:
      id: HP:0001873
      label: Thrombocytopenia
  evidence:
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "leading to severe preeclampsia including the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome"
    explanation: Low platelets are a defining component of HELLP syndrome within the preeclampsia spectrum.
- name: Elevated hepatic transaminases
  category: Clinical
  description: >
    Elevated circulating hepatic transaminase concentrations reflecting liver
    involvement, a criterion for severe features and a component of HELLP
    syndrome.
  phenotype_term:
    preferred_term: Elevated circulating hepatic transaminase concentration
    term:
      id: HP:0002910
      label: Elevated circulating hepatic transaminase concentration
  evidence:
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "leading to severe preeclampsia including the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome"
    explanation: Elevated liver enzymes are a defining feature of HELLP syndrome.
- name: Seizures (eclampsia)
  category: Clinical
  description: >
    New-onset tonic-clonic seizures in a woman with preeclampsia, defining
    the transition to eclampsia. Represents a severe neurological complication
    that can occur antepartum, intrapartum, or postpartum.
  phenotype_term:
    preferred_term: Seizure
    term:
      id: HP:0001250
      label: Seizure
  evidence:
  - reference: PMID:35177220
    reference_title: "Preeclampsia and eclampsia: the conceptual evolution of a syndrome."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "once thought to be a disease of the central nervous system, recognized by the occurrence of seizures (ie, eclampsia)"
    explanation: Eclamptic seizures are the historically defining severe complication of preeclampsia.
- name: Headache
  category: Clinical
  description: >
    Severe, persistent headache that is a warning sign for severe preeclampsia
    and eclampsia, indicating cerebral involvement.
  phenotype_term:
    preferred_term: Headache
    term:
      id: HP:0002315
      label: Headache
  evidence:
  - reference: PMID:39247143
    reference_title: "A Comparative Study of Oral Nifedipine and Intravenous Labetalol for Acute Hypertensive Management in Pregnancy: Assessing Feto-Maternal Outcomes in a Hospital-based Randomized Control Trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Severe preeclampsia is defined as blood pressure (BP) >160/110 mmHg with warning signs such as headache, blurring of vision, and epigastric pain."
    explanation: Explicitly identifies headache as a warning sign of severe preeclampsia.
- name: Visual disturbances
  category: Clinical
  description: >
    Blurred vision and other visual disturbances are warning signs of severe
    preeclampsia, reflecting cerebral edema and vasospasm.
  phenotype_term:
    preferred_term: Blurred vision
    term:
      id: HP:0000622
      label: Blurred vision
  evidence:
  - reference: PMID:39247143
    reference_title: "A Comparative Study of Oral Nifedipine and Intravenous Labetalol for Acute Hypertensive Management in Pregnancy: Assessing Feto-Maternal Outcomes in a Hospital-based Randomized Control Trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Severe preeclampsia is defined as blood pressure (BP) >160/110 mmHg with warning signs such as headache, blurring of vision, and epigastric pain."
    explanation: Explicitly identifies blurring of vision as a warning sign of severe preeclampsia.
- name: Intrauterine growth retardation
  category: Clinical
  description: >
    Fetal growth restriction due to impaired uteroplacental perfusion from
    defective spiral artery remodeling. More common in early-onset preeclampsia.
  phenotype_term:
    preferred_term: Intrauterine growth retardation
    term:
      id: HP:0001511
      label: Intrauterine growth retardation
  evidence:
  - reference: PMID:14764923
    reference_title: "Circulating angiogenic factors and the risk of preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Alterations in the levels of sFlt-1 and free PlGF were greater in women with an earlier onset of preeclampsia and in women in whom preeclampsia was associated with a small-for-gestational-age infant."
    explanation: Links angiogenic factor alterations to small-for-gestational-age infants in preeclampsia.
- name: Hemolytic anemia
  category: Clinical
  subtype: HELLP
  description: >
    Microangiopathic hemolytic anemia as part of HELLP syndrome, reflecting
    erythrocyte destruction in damaged microvasculature.
  phenotype_term:
    preferred_term: Hemolytic anemia
    term:
      id: HP:0001878
      label: Hemolytic anemia
  evidence:
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "leading to severe preeclampsia including the HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome"
    explanation: Hemolysis is a defining component of HELLP syndrome.
- name: Pulmonary edema
  category: Clinical
  description: >
    Pulmonary edema due to increased vascular permeability and fluid overload,
    a severe complication of preeclampsia.
  phenotype_term:
    preferred_term: Pulmonary edema
    term:
      id: HP:0100598
      label: Pulmonary edema
  notes: >
    Pulmonary edema is a recognized severe complication of preeclampsia,
    resulting from endothelial dysfunction, decreased oncotic pressure,
    and iatrogenic fluid overload. It is included in ACOG criteria for
    severe features of preeclampsia.
biochemical:
- name: Elevated sFlt-1
  presence: Elevated
  context: diagnostic biomarker
  notes: >
    Elevated circulating soluble fms-like tyrosine kinase 1 (sFlt-1/sVEGFR1),
    a decoy VEGF receptor produced by the ischemic placenta that sequesters
    VEGF and PlGF, disrupting endothelial function.
  evidence:
  - reference: PMID:14764923
    reference_title: "Circulating angiogenic factors and the risk of preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "At the onset of clinical disease, the mean serum level in the women with preeclampsia was 4382 pg per milliliter, as compared with 1643 pg per milliliter in controls with fetuses of similar gestational age (P<0.001)."
    explanation: Quantifies the elevation of sFlt-1 in preeclampsia versus controls.
- name: Decreased PlGF
  presence: Decreased
  context: diagnostic biomarker
  notes: >
    Reduced circulating free placental growth factor (PlGF), sequestered by
    excess sFlt-1. Low PlGF precedes clinical onset and is an early predictive
    biomarker.
  evidence:
  - reference: PMID:14764923
    reference_title: "Circulating angiogenic factors and the risk of preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The PlGF levels were significantly lower in the women who later had preeclampsia than in the controls beginning at 13 to 16 weeks of gestation (mean, 90 pg per milliliter vs. 142 pg per milliliter, P=0.01)"
    explanation: Shows that PlGF depression begins early in the second trimester before clinical disease.
- name: Elevated soluble endoglin
  presence: Elevated
  context: diagnostic biomarker
  notes: >
    Elevated circulating soluble endoglin (sEng), a TGF-beta coreceptor
    released by the placenta that inhibits TGF-beta signaling and impairs
    eNOS activation, contributing to endothelial dysfunction.
  evidence:
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "We report a novel placenta-derived soluble TGF-beta coreceptor, endoglin (sEng), which is elevated in the sera of preeclamptic individuals, correlates with disease severity and falls after delivery."
    explanation: Identifies elevated sEng as correlating with disease severity.
genetic:
- name: FLT1
  gene_term:
    preferred_term: FLT1
    term:
      id: hgnc:3763
      label: FLT1
  association: Risk Factor
  notes: >
    Encodes fms-like tyrosine kinase 1 (VEGFR1). Alternative splicing produces
    the soluble isoform sFlt-1, which is overexpressed by the preeclamptic
    placenta and acts as a decoy receptor sequestering VEGF and PlGF.
    Polymorphisms in FLT1 are associated with preeclampsia susceptibility.
  evidence:
  - reference: PMID:39062815
    reference_title: "A Narrative Review on the Pathophysiology of Preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Genetic and epigenetic modifications, including polymorphisms in the Fms-like tyrosine kinase 1 (FLT1) gene and altered microRNA (miRNA) expression, play critical roles."
    explanation: Identifies FLT1 polymorphisms as playing a critical role in preeclampsia.
  - reference: PMID:12618519
    reference_title: "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "we confirm that placental soluble fms-like tyrosine kinase 1 (sFlt1), an antagonist of VEGF and placental growth factor (PlGF), is upregulated in preeclampsia"
    explanation: Demonstrates sFlt-1 (FLT1 gene product) upregulation in preeclamptic placentas.
- name: PGF
  gene_term:
    preferred_term: PGF
    term:
      id: hgnc:8893
      label: PGF
  association: Risk Factor
  notes: >
    Encodes placental growth factor (PlGF), a VEGF family member essential for
    placental angiogenesis. Free PlGF levels are reduced in preeclampsia due
    to sequestration by excess sFlt-1, and low PlGF is an early biomarker.
  evidence:
  - reference: PMID:14764923
    reference_title: "Circulating angiogenic factors and the risk of preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Increased levels of sFlt-1 and reduced levels of PlGF predict the subsequent development of preeclampsia."
    explanation: PlGF reduction is a key predictive feature of preeclampsia.
- name: ENG
  gene_term:
    preferred_term: ENG
    term:
      id: hgnc:3349
      label: ENG
  association: Risk Factor
  notes: >
    Encodes endoglin, a TGF-beta coreceptor. The soluble form (sEng) is
    elevated in preeclampsia and synergizes with sFlt-1 to induce severe
    disease including HELLP syndrome in animal models.
  evidence:
  - reference: PMID:16751767
    reference_title: "Soluble endoglin contributes to the pathogenesis of preeclampsia."
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: "Our results suggest that sEng may act in concert with sFlt1 to induce severe preeclampsia."
    explanation: Demonstrates the pathogenic role of soluble endoglin (ENG gene product) in severe preeclampsia.
- name: VEGFA
  gene_term:
    preferred_term: VEGFA
    term:
      id: hgnc:12680
      label: VEGFA
  association: Risk Factor
  notes: >
    Encodes vascular endothelial growth factor A, a key mediator of
    angiogenesis and endothelial homeostasis. Sequestration of free VEGF by
    excess sFlt-1 in preeclampsia contributes to endothelial dysfunction.
  evidence:
  - reference: PMID:12618519
    reference_title: "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "increased circulating sFlt1 in patients with preeclampsia is associated with decreased circulating levels of free VEGF and PlGF"
    explanation: Human clinical data showing that sFlt-1 excess sequesters free VEGF in preeclampsia patients.
  - reference: PMID:12618519
    reference_title: "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "resulting in endothelial dysfunction in vitro that can be rescued by exogenous VEGF and PlGF."
    explanation: In vitro evidence that exogenous VEGF can rescue sFlt-1-induced endothelial dysfunction.
treatments:
- name: Delivery
  description: >
    Delivery of the fetus and placenta is the only definitive treatment for
    preeclampsia. Timing depends on gestational age and severity, balancing
    maternal risk against fetal prematurity. Generally recommended at 37 weeks
    for preeclampsia without severe features, and earlier if severe features
    or maternal/fetal deterioration occurs.
  treatment_term:
    preferred_term: labor induction
    term:
      id: MAXO:0000861
      label: labor induction
  evidence:
  - reference: PMID:30792480
    reference_title: "Pre-eclampsia: pathogenesis, novel diagnostics and therapies."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "which can progress to multi-organ dysfunction, including hepatic, renal and cerebral disease, if the fetus and placenta are not delivered."
    explanation: Identifies delivery as the necessary intervention to prevent progression.
- name: Low-dose aspirin prophylaxis
  description: >
    Low-dose aspirin (150 mg daily) initiated at 11-14 weeks of gestation
    in women identified as high risk reduces the incidence of preterm
    preeclampsia by approximately 62%. This is a preventive intervention,
    not a treatment for established disease.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: acetylsalicylic acid
      term:
        id: CHEBI:15365
        label: acetylsalicylic acid
  evidence:
  - reference: PMID:28657417
    reference_title: "Aspirin versus Placebo in Pregnancies at High Risk for Preterm Preeclampsia."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Preterm preeclampsia occurred in 13 participants (1.6%) in the aspirin group, as compared with 35 (4.3%) in the placebo group (odds ratio in the aspirin group, 0.38; 95% confidence interval, 0.20 to 0.74; P=0.004)."
    explanation: The ASPRE trial demonstrated a 62% reduction in preterm preeclampsia with aspirin 150 mg daily.
- name: Magnesium sulfate for seizure prevention
  description: >
    Magnesium sulfate is the first-line agent for prevention and treatment
    of eclamptic seizures. It halves the risk of eclampsia in women with
    preeclampsia and probably reduces maternal mortality.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: magnesium sulfate
      term:
        id: CHEBI:32599
        label: magnesium sulfate
  evidence:
  - reference: PMID:12057549
    reference_title: "Do women with pre-eclampsia, and their babies, benefit from magnesium sulphate? The Magpie Trial: a randomised placebo-controlled trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Women allocated magnesium sulphate had a 58% lower risk of eclampsia (95% CI 40-71) than those allocated placebo (40, 0.8%, vs 96, 1.9%; 11 fewer women with eclampsia per 1000 women)."
    explanation: The Magpie trial demonstrated that magnesium sulfate halves eclampsia risk.
- name: Antihypertensive therapy (labetalol)
  description: >
    Labetalol is a first-line antihypertensive for acute blood pressure
    management in severe preeclampsia, used to prevent hypertensive emergencies
    and stroke.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: labetalol
      term:
        id: CHEBI:6343
        label: labetalol
  evidence:
  - reference: PMID:39247143
    reference_title: "A Comparative Study of Oral Nifedipine and Intravenous Labetalol for Acute Hypertensive Management in Pregnancy: Assessing Feto-Maternal Outcomes in a Hospital-based Randomized Control Trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Nifedipine (C17H18N2O6), labetalol (C19H24N2O3), and hydralazine (C8H8N4) are commonly used drugs, and all are recommended as first-line agents."
    explanation: Identifies labetalol as a recommended first-line agent for acute hypertensive management in pregnancy.
- name: Antihypertensive therapy (nifedipine)
  description: >
    Nifedipine is an alternative first-line oral antihypertensive for acute
    severe hypertension in preeclampsia.
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: nifedipine
      term:
        id: CHEBI:7565
        label: nifedipine
  evidence:
  - reference: PMID:39247143
    reference_title: "A Comparative Study of Oral Nifedipine and Intravenous Labetalol for Acute Hypertensive Management in Pregnancy: Assessing Feto-Maternal Outcomes in a Hospital-based Randomized Control Trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "oral nifedipine has been proposed as a first-line alternative to intravenous labetalol."
    explanation: Identifies nifedipine as a first-line alternative antihypertensive for severe preeclampsia.
📚

References & Deep Research

Deep Research

1
Research Summary: Preeclampsia (MONDO:0005081) ▸

Research Summary: Preeclampsia (MONDO:0005081)

This is assigned to @nlharris — skipping autonomous curation. This summary is intended as a research aid for the curator.

Disease Overview

Preeclampsia is a multisystem pregnancy disorder affecting 2–8% of pregnancies worldwide, accounting for >50,000 maternal and >500,000 fetal deaths annually. It is defined by new-onset hypertension (≥140/90 mmHg) developing after 20 weeks of gestation, typically accompanied by proteinuria or evidence of end-organ damage. It is the dominant clinical manifestation in a spectrum that includes gestational hypertension, HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets), and eclampsia (seizures).

The condition is now understood as a vascular disorder unmasked by pregnancy rather than a hypertensive disorder per se — the placenta is the central driver, and delivery is the only definitive cure.

Key ACOG diagnostic update (2019+): Proteinuria is no longer required if severe hypertension coexists with end-organ damage (thrombocytopenia, renal insufficiency, impaired liver function, pulmonary edema, or new-onset headache/visual symptoms).

Pathophysiology: The Two-Stage Model

The dominant framework is a two-stage model (Roberts/Hubel, extensively reviewed):

STAGE 1 (Silent, pre-clinical)         STAGE 2 (Clinical maternal syndrome)
─────────────────────────────           ─────────────────────────────────────
Defective trophoblast invasion   →  →   Anti-angiogenic factors released
+ Failed spiral artery remodeling       into maternal circulation
                   →  →   Endothelial dysfunction (systemic)
                         → Hypertension
                         → Proteinuria (glomerular endotheliosis)
                         → HELLP, eclampsia

This explains the early-onset/late-onset split: early-onset (< 34 wks) is dominated by placental failure (Stage 1); late-onset (≥ 34 wks) by maternal constitutional predisposition and endothelial vulnerability.

Pathophysiology Nodes (Suggested Structure)

Node 1: Defective Trophoblast Invasion and Spiral Artery Remodeling

  • Normally, extravillous trophoblasts (EVTs) invade the spiral arteries and replace vascular smooth muscle, transforming them from high-resistance to high-capacitance vessels
  • In preeclampsia, this invasion is shallow; spiral arteries remain narrow, tortuous, and high-resistance
  • Results in placental ischemia and hypoxia

Key mechanisms: - Impaired uterine NK (uNK) cell tolerance and signaling (KIR/HLA-C interactions at the decidua-trophoblast interface) - HLA-G expressed on EVTs normally dampens NK cytotoxicity; this axis is disrupted in PE - Dysregulated TGF-β, VEGF, and HIF-1α signaling in the decidua

Key cell types: - Extravillous trophoblast (EVT): CL:0000351 (trophoblast) / extravillous subtype - Uterine natural killer cell: CL:0000623 (natural killer cell) — decidual NK cells are CL:0002362 - Decidual stromal cell

Key biological processes: - Trophoblast cell migration / invasion: GO:0001753 (trophoblast giant cell differentiation — verify specificity) - GO:0001570 (vasculogenesis) - GO:0035441 (cell migration involved in vasculogenesis) - Response to hypoxia: GO:0001666

Node 2: Placental Oxidative Stress and sFlt-1 Overproduction

  • Ischemic/hypoxic placenta upregulates HIF-1α, triggering massive production of sFlt-1 (soluble VEGF receptor-1, a splice variant of FLT1)
  • sFlt-1 is a potent decoy receptor that sequesters circulating VEGF and PlGF (placental growth factor)
  • Result: markedly reduced free VEGF/PlGF → anti-angiogenic state in the mother
  • Soluble endoglin (sEng), also released by the hypoxic placenta, inhibits TGF-β signaling and amplifies endothelial damage
  • The sFlt-1:PlGF ratio is now used clinically (ratio >38 predicts adverse outcomes within 4 weeks; EMA/FDA approved)

Key genes (need OAK verification of HGNC IDs): - FLT1 (hgnc:3738 — verify) — encodes Flt-1; alternative splicing generates sFlt-1 - PGF (hgnc:8982 — verify) — encodes PlGF - ENG (hgnc:3349 — verify) — encodes endoglin; shed as sEng - VEGFA (hgnc:12680 — verify) — primary target sequestered by sFlt-1

Key biological processes: - GO:0001525 — angiogenesis - GO:0048010 — VEGF receptor signaling pathway - GO:0001666 — cellular response to hypoxia - HIF-1 signaling / hypoxia-inducible factor pathway

Node 3: Maternal Endothelial Dysfunction and Multi-Organ Injury

  • Circulating sFlt-1, sEng, syncytiotrophoblast microparticles, and inflammatory mediators damage the systemic maternal endothelium
  • Endothelial activation → reduced NO production, endothelin-1 upregulation → vasoconstriction → hypertension
  • Kidney: Glomerular endotheliosis (pathognomonic lesion — swelling of glomerular endothelial cells, effacement of fenestrae) → proteinuria
  • Liver: Hepatic sinusoidal obstruction, periportal necrosis → elevated transaminases; capsular distension → epigastric/RUQ pain; HELLP
  • Brain: Posterior reversible encephalopathy syndrome (PRES), cerebral edema, seizures (eclampsia) — cerebrovascular autoregulation failure
  • Coagulation: Endothelial activation triggers DIC-spectrum, thrombocytopenia (HELLP)
  • Placenta: Decidual vasculopathy, infarcts → fetal growth restriction, placental abruption

Key cell types: - Vascular endothelial cell: CL:0000071 (blood vessel endothelial cell) - Glomerular endothelial cell: CL:1000850 (glomerular endothelial cell — verify) - Syncytiotrophoblast: CL:0000525 (syncytiotrophoblast — verify CL ID) - Platelet: CL:0000233

Key biological processes: - GO:0008217 — regulation of blood pressure - GO:0045087 — innate immune response - GO:0042493 — response to drug (for treatment nodes) - Nitric oxide signaling / endothelial NOS pathway - GO:0006954 — inflammatory response - Complement activation: GO:0006956

Clinical Phenotypes (Suggested HPO Terms)

Phenotype HP term Notes
Hypertension HP:0000822 Core diagnostic criterion
Proteinuria HP:0000093 Common but not required
Edema HP:0000969 (peripheral) Classic but removed from criteria
Thrombocytopenia HP:0001873 HELLP; <100K/µL is threshold
Elevated hepatic transaminases HP:0002910 HELLP component
Seizures HP:0001250 Defines eclampsia
Headache HP:0002315 New-onset, unresponsive to medication
Intrauterine growth retardation HP:0001511 Fetal consequence
Renal insufficiency HP:0000083 Cr >1.1 mg/dL
Visual impairment HP:0000505 Scotomata, blurred vision
Hemolysis HP:0001878 HELLP — microangiopathic
Pulmonary edema HP:0100598 Severe feature
Abnormal platelet morphology — see thrombocytopenia
Placental abruption HP:0011410 — verify Obstetric complication

Subtypes

The entry should have at least two main subtypes: - Early-onset (< 34 weeks): Placenta-driven, more severe, higher sFlt-1, more associated with FGR; higher risk - Late-onset (≥ 34 weeks): More maternal constitutional; less placental pathology; more common but generally less severe - HELLP syndrome: Can be considered a severe variant with microangiopathic hemolysis, elevated LFTs, low platelets; may occur without classic hypertension/proteinuria - Superimposed preeclampsia: On a background of chronic hypertension

Treatments

Treatment Term Notes
Low-dose aspirin (prevention) MAXO:0000058 + CHEBI:29177 (aspirin) USPSTF Grade B; 81 mg/day from 12–28 wks
Magnesium sulfate (seizure prophylaxis) MAXO:0000058 + CHEBI:32006 (verify) Reduces eclampsia 58%; IV loading dose
Labetalol (BP control) MAXO:0000058 + CHEBI:6522 (labetalol — verify) First-line IV acute
Nifedipine (BP control) MAXO:0000058 + CHEBI:7565 (nifedipine — verify) Oral; first-line
Hydralazine MAXO:0000058 + CHEBI:5757 (hydralazine — verify) IV acute management
Delivery MAXO:0000004 (surgical procedure) or MAXO:0001187 Definitive treatment
Calcium supplementation (prevention) MAXO:0000088 (dietary intervention) Effective in low-calcium populations
Corticosteroids (fetal lung maturation) MAXO:0000647 + CHEBI:16723 (betamethasone — verify) If < 34 wks gestation

Key Evidence References (Verified PMIDs)

The following PMIDs were confirmed by direct abstract retrieval:

  1. PMID:30792480 — Phipps et al. 2019, Nat Rev Nephrology — "Pre-eclampsia: pathogenesis, novel diagnostics and therapies." Comprehensive mechanistic review covering sFlt-1/sEng/PlGF, endothelial dysfunction, renal glomerular endotheliosis, and emerging therapies. Highly recommended as primary reference.

  2. PMID:35177220 — Erez et al. 2022, Am J Obstet Gynecol — "Preeclampsia and eclampsia: the conceptual evolution of a syndrome." Covers the historical shift from neurological → vascular conceptualization; early vs. late onset subtypes; role of antiangiogenic factors.

  3. PMID:34033373 — Karrar et al. 2024, StatPearls — Comprehensive overview of diagnostic criteria, pathophysiology (uteroplacental ischemia), and management.

  4. PMID:32443079 — ACOG Practice Bulletin #222, 2020, Obstet Gynecol — Clinical guideline; the rate of preeclampsia increased 25% between 1987–2004; management thresholds and protocols.

Additional high-priority references to fetch and verify (titles confirmed, PMIDs need just fetch-reference verification):

  • Maynard et al. (2003) J Clin Invest — "Excess placental soluble fms-like tyrosine kinase 1 (sFlt1) may contribute to endothelial dysfunction, hypertension, and proteinuria in preeclampsia" — The landmark animal model paper establishing sFlt-1 causality.
  • Levine et al. (2004) N Engl J Med — "Circulating angiogenic factors and the risk of preeclampsia" — Prospective clinical cohort showing sFlt-1 rises and PlGF falls weeks before clinical PE onset.
  • Redman & Sargent (2005) Science — "Latest advances in understanding preeclampsia" — Overview of immune and vascular mechanisms.
  • Verlohren et al. (2010/2012) Hypertension — Established the sFlt-1:PlGF ratio clinical cutoff of 38.
  • Staff et al. (2019) — Clinical use of angiogenic biomarkers in preeclampsia.

Orphanet / Structured Sources

  • Orphanet ORPHA code for pre-eclampsia: likely ORPHA:275555 — run just fetch-reference ORPHA:275555 to verify and check for definition, prevalence, and gene-disease associations that can be cited as ORPHA:275555 evidence items.

Suggested Module Conformance

Preeclampsia does not appear to conform to the existing fibrotic_response or immune_checkpoint_blockade modules. The disease may warrant a future placental_vascular_dysfunction module given the conserved sFlt-1/PlGF anti-angiogenic mechanism also seen in fetal growth restriction, spontaneous preterm birth, and HELLP syndrome.

The complement-driven endothelial damage node could potentially align with modules used in other thrombotic microangiopathy entries (e.g., aHUS) if those are curated.

Long-term Consequences (for progression or outcomes section)

  • Women with prior preeclampsia have 2× lifetime risk of cardiovascular disease, 2–4× risk of hypertension, and 2× risk of stroke
  • Preterm delivery and FGR are the primary fetal consequences
  • Recurrence rate in subsequent pregnancies: 15–25% (higher if early-onset index pregnancy)

Summary generated by Claude Code summarization agent from PubMed abstracts and authoritative review sources. All PMIDs must be verified with just fetch-reference before use as snippets.