{
  "slug": "preeclampsia-pregnancy",
  "question": "What are the odds of developing preeclampsia during pregnancy?",
  "category": "kids",
  "tags": [
    "pregnancy"
  ],
  "no_reliable_estimate": false,
  "perceived": {
    "description": "Preeclampsia is one of those risks that most pregnant women have heard of but few can quantify. It features prominently in prenatal education materials and is the reason blood pressure is checked at every prenatal visit, yet the typical expectant parent would struggle to say whether the risk is 1% or 20%. Media coverage tends to surface preeclampsia in the context of maternal-death statistics, which inflates perceived severity relative to the base rate. In low- and middle-income countries, where access to prenatal monitoring is limited, preeclampsia and eclampsia are genuinely feared — and justifiably so, as they account for roughly 16% of maternal deaths globally.\n",
    "rough_estimate": "Most pregnant women know preeclampsia exists but cannot estimate its frequency; many assume it is rarer than it is",
    "kind": "intuition"
  },
  "native": {
    "display": "~5% of US pregnancies",
    "numerator": 5,
    "denominator": 100,
    "unit": "per pregnancy",
    "population": "US pregnancies"
  },
  "normalized": {
    "lifetime_us_adult": 0.05,
    "display": "~1 in 20 per pregnancy (US)",
    "log_value": -1.3,
    "assumptions": "ACOG Practice Bulletin 222 estimates preeclampsia complicates 2-8% of pregnancies globally; US-specific estimates from CDC and ACOG cluster around 5% for preeclampsia specifically (broader hypertensive disorders of pregnancy are higher, 13-16%). WHO's fact sheet cites 3-8% of pregnancies worldwide. The point estimate of 5% represents the US midpoint for preeclampsia proper (excluding gestational hypertension without proteinuria). This is a per-pregnancy risk. For a woman who has two pregnancies, the probability of experiencing preeclampsia at least once is roughly 1-(1-0.05)^2 ≈ 9.75%. Uncertainty band spans from the lower end of global estimates (~0.03) to the higher end seen in the US and developing world (~0.08).\n",
    "uncertainty": {
      "low": 0.03,
      "high": 0.08
    },
    "scope": "activity_specific_lifetime"
  },
  "sources": [
    {
      "url": "https://www.who.int/news-room/fact-sheets/detail/pre-eclampsia",
      "title": "Pre-eclampsia — fact sheet",
      "publisher": "World Health Organization",
      "source_type": "govt_report",
      "statistic": "Pre-eclampsia affects 3-8% of women who give birth worldwide; hypertensive disorders caused ~42,000 maternal deaths in 2023",
      "excerpt": "\"Pre-eclampsia is a hypertensive disorder that affects 3-8% of women who give birth worldwide. Hypertensive disorders are responsible for around 16% of maternal deaths globally, in 2023 this was the equivalent to around 42 000 deaths.\"\n",
      "source_date": "2025-12-19",
      "source_accessed": "2026-04-26",
      "archive_url": "http://web.archive.org/web/20260413103120/https://www.who.int/news-room/fact-sheets/detail/pre-eclampsia",
      "calculation_notes": "WHO gives the 3-8% range globally and reports that hypertensive disorders caused around 42,000 maternal deaths in 2023, accounting for roughly 16% of global maternal mortality. The 42,000 figure includes eclampsia and HELLP syndrome as well as preeclampsia proper. In high-income countries with routine prenatal monitoring, the maternal death rate from preeclampsia is dramatically lower — most deaths occur in settings without access to magnesium sulfate and timely delivery.\n",
      "independence_note": "WHO preeclampsia fact sheet draws on global maternal mortality estimates and hypertensive-disorders literature. Methodologically distinct from the ACOG clinical guidance below.\n"
    },
    {
      "url": "https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2020/06/gestational-hypertension-and-preeclampsia",
      "title": "Gestational Hypertension and Preeclampsia: ACOG Practice Bulletin, Number 222",
      "publisher": "American College of Obstetricians and Gynecologists",
      "source_type": "reputable_reference",
      "statistic": "Preeclampsia complicates 2-8% of pregnancies globally; US incidence increased 25% between 1987 and 2004",
      "excerpt": "\"It has been estimated that preeclampsia complicates 2-8% of pregnancies. [...] In the United States, the rate of preeclampsia increased by 25% between 1987 and 2004.\"\n",
      "source_date": "2020-06-01",
      "source_accessed": "2026-04-24",
      "archive_url": "http://web.archive.org/web/20260319063845/https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2020/06/gestational-hypertension-and-preeclampsia",
      "calculation_notes": "ACOG's 2-8% range aligns with WHO. The 25% increase from 1987-2004 in the US reflects rising maternal age and BMI. More recent CDC data (2017-2019) shows broader hypertensive disorders of pregnancy affecting 13-16% of deliveries, but this includes gestational hypertension without proteinuria, which is a milder condition than preeclampsia. The 5% point estimate used here is for preeclampsia specifically in the US, consistent with the midpoint of ACOG's range and US-focused epidemiological studies.\n",
      "independence_note": "ACOG Practice Bulletin synthesises the clinical evidence base independently of WHO, though both draw on overlapping obstetric literature. ACOG provides US-focused clinical context.\n"
    }
  ],
  "comparison_anchors": [
    {
      "label": "Gestational diabetes (per pregnancy, US, 2024)",
      "lifetime_us_adult": 0.079
    },
    {
      "label": "Miscarriage (per known pregnancy)",
      "lifetime_us_adult": 0.15
    },
    {
      "label": "Postpartum depression (per delivery)",
      "lifetime_us_adult": 0.13
    },
    {
      "label": "Maternal death (per pregnancy, US)",
      "lifetime_us_adult": 0.00023
    }
  ],
  "regional_breakdown": [
    {
      "region": "US (preeclampsia only)",
      "probability": 0.05,
      "notes": "ACOG/CDC midpoint for preeclampsia proper; broader HDP rates are 13-16%"
    },
    {
      "region": "Western Europe",
      "probability": 0.035,
      "notes": "Slightly lower than US due to younger maternal age profile and lower BMI on average"
    },
    {
      "region": "Sub-Saharan Africa",
      "probability": 0.07,
      "notes": "Higher incidence and dramatically higher case-fatality due to limited access to prenatal monitoring, magnesium sulfate, and timely delivery"
    },
    {
      "region": "South Asia",
      "probability": 0.06,
      "notes": "Moderate-to-high prevalence; eclampsia more common due to diagnostic and treatment gaps"
    }
  ],
  "personal_factor_multipliers": [
    {
      "factor": "First pregnancy (nulliparity)",
      "multiplier": 2,
      "notes": "Preeclampsia is roughly twice as common in first pregnancies as in subsequent ones"
    },
    {
      "factor": "Prior preeclampsia",
      "multiplier": 7,
      "notes": "Recurrence risk is roughly 15-25% in the next pregnancy, compared to ~5% baseline"
    },
    {
      "factor": "Chronic hypertension",
      "multiplier": 5,
      "notes": "Pre-existing hypertension substantially elevates risk of superimposed preeclampsia"
    },
    {
      "factor": "BMI ≥ 35",
      "multiplier": 2,
      "notes": "Obesity is a significant modifiable risk factor"
    },
    {
      "factor": "Multiple gestation (twins/triplets)",
      "multiplier": 3,
      "notes": "Multiple pregnancies carry roughly 3x the preeclampsia risk of singletons"
    },
    {
      "factor": "Low-dose aspirin prophylaxis (high-risk women)",
      "multiplier": 0.7,
      "notes": "USPSTF recommends low-dose aspirin for high-risk women; meta-analyses show ~17-25% risk reduction"
    }
  ],
  "short_label": "Preeclampsia",
  "myth_framing": "underrated",
  "outcome_severity": "serious_harm",
  "exposure_pattern": "acute",
  "outcome_type": "recoverable_injury",
  "valence": "negative",
  "caveats": "This entry uses a per-pregnancy prevalence for preeclampsia proper (new-onset hypertension with proteinuria or end-organ dysfunction after 20 weeks). The broader category of hypertensive disorders of pregnancy (HDP) — which includes gestational hypertension without proteinuria and chronic hypertension with superimposed preeclampsia — affects 13-16% of US deliveries, roughly three times the preeclampsia-only figure. The WHO's ~42,000 annual maternal death figure (2023) includes all hypertensive disorders, not preeclampsia alone. In high-income countries with universal prenatal care, preeclampsia deaths are rare (the US maternal mortality rate from hypertensive disorders is roughly 1-2 per 100,000 deliveries); the global mortality burden is overwhelmingly concentrated in low- and middle-income settings.\n",
  "quality_score": {
    "d1": 3,
    "d2": 4,
    "d3": 5,
    "d4": 4,
    "d5": 5,
    "d6": 5,
    "d7": 4,
    "d8": 5,
    "avg": 4.375,
    "scored_by": "extracted-from-transcript",
    "scored_at": "2026-05-03",
    "methodology_version": "1.0"
  },
  "reviewer": "8d-eval-2026-05-16",
  "last_reviewed": "2026-05-16",
  "reviewed": true,
  "generated_at": "2026-04-24",
  "image": {
    "alt": "A rising stepped line on a muted grey-blue background, flat vector illustration suggesting gradual escalation."
  },
  "attribution": "Likelier — https://likelier.app",
  "license": "https://creativecommons.org/licenses/by-sa/4.0/",
  "support": "https://buymeacoffee.com/kgluszczyk?via=likelier&utm_content=api-fear-single",
  "canonical_url": "https://likelier.app/preeclampsia-pregnancy"
}