{
  "slug": "miscarriage-recognized-pregnancy",
  "question": "What are the odds of miscarriage after a recognized pregnancy?",
  "category": "kids",
  "tags": [
    "pregnancy"
  ],
  "no_reliable_estimate": false,
  "perceived": {
    "description": "Miscarriage is widely misunderstood as a rare event. In a national survey of over 1,000 US adults, 55% believed miscarriage occurs in 5% or fewer of all pregnancies — roughly a threefold underestimate. Among those who had experienced a miscarriage, 47% reported feeling guilty and 41% felt they were alone, suggesting the true prevalence is hidden by silence rather than by absence.\n",
    "rough_estimate": "~5% or less (most common public guess)",
    "kind": "survey",
    "survey_source": {
      "title": "A National Survey on Public Perceptions of Miscarriage",
      "publisher": "Obstetrics & Gynecology (Bardos et al.)",
      "url": "https://pubmed.ncbi.nlm.nih.gov/26000502/",
      "year": 2015
    }
  },
  "native": {
    "display": "~1 in 7 recognized pregnancies",
    "numerator": 1,
    "denominator": 7,
    "unit": "per clinically recognized pregnancy",
    "population": "women with clinically recognized pregnancies"
  },
  "normalized": {
    "lifetime_us_adult": 0.15,
    "display": "~15% per recognized pregnancy",
    "log_value": -0.82,
    "assumptions": "Central estimate of 15% drawn from the 11-22% range in Ammon Avalos et al. (2012) and the 10-20% figure cited by March of Dimes and ACOG. This is per recognized pregnancy, not per woman or per lifetime. Losses before clinical recognition (biochemical pregnancies) are excluded and would roughly double the total rate.\n",
    "uncertainty": {
      "low": 0.1,
      "high": 0.22
    },
    "scope": "activity_specific_lifetime"
  },
  "sources": [
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/22511535/",
      "title": "A systematic review to calculate background miscarriage rates using life table analysis",
      "publisher": "Birth Defects Research Part A: Clinical and Molecular Teratology",
      "source_type": "peer_reviewed",
      "statistic": "Cumulative risk of miscarriage weeks 5-20: 11-22 per 100 women",
      "excerpt": "\"the cumulative risk of miscarriage for weeks 5 through 20 of gestation ranged from 11 miscarriages per 100 women to 22 miscarriages per 100 women (11-22%).\"\n",
      "source_date": "2012-06-01",
      "source_accessed": "2026-04-11",
      "archive_url": "https://web.archive.org/web/20260413180130/https://pubmed.ncbi.nlm.nih.gov/22511535/",
      "calculation_notes": "Life-table analysis across multiple cohort studies. The 11-22% range reflects variation across study populations and gestational-age cutoffs. Midpoint ~15% used as native estimate. Weekly hazard peaks before week 13 at >20 per 1,000 women-weeks.\n",
      "independence_note": "Systematic review pooling US and European cohort studies. Methodologically independent of Magnus et al.'s Norwegian registry data, though both ultimately describe clinically recognized pregnancies in high-income populations.\n"
    },
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/30894356/",
      "title": "Role of maternal age and pregnancy history in risk of miscarriage: prospective register based study",
      "publisher": "BMJ",
      "source_type": "peer_reviewed",
      "statistic": "Miscarriage risk lowest at age 25-29 (10%), rising to 53% at age 45+",
      "excerpt": "\"The risk of miscarriage was lowest in women aged 25-29 (10%), and rose rapidly after age 30, reaching 53% in women aged 45 and over.\"\n",
      "source_date": "2019-03-20",
      "source_accessed": "2026-04-11",
      "archive_url": "https://web.archive.org/web/20260413180211/https://pubmed.ncbi.nlm.nih.gov/30894356/",
      "calculation_notes": "Norwegian registry study (421,201 pregnancies). Provides the age gradient used for personal_factor_multipliers. Baseline ~10% at 25-29 anchors the age-specific curve.\n",
      "independence_note": "Norwegian registry data is independent of the Ammon Avalos systematic review, which drew primarily from US and European cohort studies.\n"
    },
    {
      "url": "https://pubmed.ncbi.nlm.nih.gov/26000502/",
      "title": "A National Survey on Public Perceptions of Miscarriage",
      "publisher": "Obstetrics & Gynecology",
      "source_type": "peer_reviewed",
      "statistic": "55% of respondents believed miscarriage occurs in 5% or less of pregnancies",
      "excerpt": "\"Respondents to our survey erroneously believed that miscarriage is a rare complication of pregnancy, with the majority believing that it occurred in 5% or less\"\n",
      "source_date": "2015-06-01",
      "source_accessed": "2026-04-11",
      "archive_url": "http://web.archive.org/web/20260110023612/https://pubmed.ncbi.nlm.nih.gov/26000502/",
      "calculation_notes": "Used for the perceived risk estimate. Survey of 1,084 US adults; 55% placed miscarriage at ≤5%, which is roughly 3x lower than the epidemiological consensus of 10-20%.\n",
      "independence_note": "Public-perception survey data, entirely separate from the epidemiological sources. Used only for the perceived-risk axis; does not feed into the probability estimate.\n"
    },
    {
      "url": "https://www.marchofdimes.org/find-support/topics/miscarriage-loss-grief/miscarriage",
      "title": "Miscarriage",
      "publisher": "March of Dimes",
      "source_type": "reputable_reference",
      "statistic": "10 to 20 percent of known pregnancies end in miscarriage",
      "excerpt": "\"It's estimated that between 10 to 20 in 100 known pregnancies (10 to 20 percent) end in miscarriage.\"\n",
      "source_date": "2024-10-01",
      "source_accessed": "2026-04-11",
      "archive_url": "https://web.archive.org/web/20260420044114/https://www.marchofdimes.org/find-support/topics/miscarriage-loss-grief/miscarriage",
      "calculation_notes": "Patient-facing summary consistent with ACOG guidance and the Ammon Avalos systematic review. Used as corroborating reputable reference for the 10-20% headline range.\n",
      "independence_note": "March of Dimes cites ACOG and underlying literature, so this is a dependent summary rather than an independent data source.\n"
    }
  ],
  "comparison_anchors": [
    {
      "label": "Appendicitis (lifetime, US adult)",
      "lifetime_us_adult": 0.07
    },
    {
      "label": "Type 2 diabetes diagnosis (lifetime, US adult)",
      "lifetime_us_adult": 0.4
    }
  ],
  "regional_breakdown": [
    {
      "region": "Gestational weeks 5-6",
      "probability": 0.1,
      "notes": "Highest weekly hazard; ~10% cumulative risk by end of week 6"
    },
    {
      "region": "After cardiac activity at 8 weeks",
      "probability": 0.05,
      "notes": "Risk drops roughly by half once fetal heartbeat is confirmed"
    },
    {
      "region": "After 12 weeks (second trimester)",
      "probability": 0.02,
      "notes": "~1-2% residual risk; often called 'late miscarriage' after this point"
    },
    {
      "region": "After 20 weeks",
      "probability": 0.005,
      "notes": "Classified as stillbirth rather than miscarriage in most jurisdictions"
    }
  ],
  "personal_factor_multipliers": [
    {
      "factor": "Maternal age 20-24",
      "multiplier": 0.7,
      "notes": "Magnus et al. 2019: slightly below the 25-29 baseline"
    },
    {
      "factor": "Maternal age 25-29 (baseline)",
      "multiplier": 1,
      "notes": "Reference group; ~10% miscarriage rate (Magnus et al. 2019)"
    },
    {
      "factor": "Maternal age 30-34",
      "multiplier": 1.5,
      "notes": "~15% risk (Magnus et al. 2019)"
    },
    {
      "factor": "Maternal age 35-39",
      "multiplier": 2,
      "notes": "~20% risk; often cited as the 'advanced maternal age' threshold"
    },
    {
      "factor": "Maternal age 40-44",
      "multiplier": 4,
      "notes": "~40% risk (Magnus et al. 2019)"
    },
    {
      "factor": "Maternal age 45+",
      "multiplier": 5.3,
      "notes": "~53% risk (Magnus et al. 2019)"
    },
    {
      "factor": "One prior miscarriage",
      "multiplier": 1.5,
      "notes": "Magnus et al. 2019: recurrence risk is modestly elevated"
    },
    {
      "factor": "Three or more prior miscarriages",
      "multiplier": 2.5,
      "notes": "Recurrent pregnancy loss substantially increases the per-pregnancy risk"
    }
  ],
  "short_label": "Miscarriage",
  "myth_framing": "calibrated",
  "outcome_severity": "serious_harm",
  "exposure_pattern": "acute",
  "outcome_type": "recoverable_injury",
  "valence": "negative",
  "caveats": "The 10-20% figure applies only to clinically recognized pregnancies — those confirmed by positive test or ultrasound. Including biochemical pregnancies (losses before clinical detection) roughly doubles the total to ~30% or more. The gestational-week breakdown uses pooled estimates and varies by detection method, maternal health, and study design. Stillbirth (loss after 20 weeks) is a separate statistic not included here.\n",
  "quality_score": {
    "d1": 5,
    "d2": 5,
    "d3": 4,
    "d4": 4,
    "d5": 4,
    "d6": 4,
    "d7": 5,
    "d8": 4,
    "avg": 4.375,
    "scored_by": "claude-code-8d",
    "scored_at": "2026-05-25",
    "methodology_version": "1.2"
  },
  "reviewer": "likelier-phase-5-agent",
  "last_reviewed": "2026-04-12",
  "reviewed": true,
  "generated_at": "2026-04-11",
  "image": {
    "alt": "A single small seedling in a muted terracotta pot against a pale grey background, flat vector illustration."
  },
  "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/miscarriage-recognized-pregnancy"
}