What are the odds of miscarriage after a recognized pregnancy?
Evidence quality 4.38/5
Eight-dimension review score against the quality rubric . Each dimension scored 1–5.
- D1 Source grounding
- 5/5
- D2 Source authority
- 5/5
- D3 Arithmetic
- 4/5
- D4 Uncertainty
- 4/5
- D5 Scope
- 4/5
- D6 Prose
- 4/5
- D7 Perception honesty
- 5/5
- D8 Caveat completeness
- 4/5
Lifetime probability · lifetime, activity-specific
1 in 6.7
15% lifetime chance
range 1 in 10 to 1 in 4.5
● your factors — click this risk ▾ to reveal
≈ As likely as
Perceived
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.
Rough estimate: ~5% or less (most common public guess)
Actual
~1 in 7 recognized pregnancies
women with clinically recognized pregnancies
Show derivation
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.
Caveats: The 10-20% figure applies only to clinically recognized pregnancies — those conf…
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.
Regional breakdown
The headline figure averages across very different populations. Here’s how the probability varies by geography or context:
| Region / context | Lifetime probability | Notes |
|---|---|---|
| Gestational weeks 5-6 | 1 in 10 |
Highest weekly hazard; ~10% cumulative risk by end of week 6 |
| After cardiac activity at 8 weeks | 1 in 20 |
Risk drops roughly by half once fetal heartbeat is confirmed |
| After 12 weeks (second trimester) | 1 in 50 |
~1-2% residual risk; often called 'late miscarriage' after this point |
| After 20 weeks | 1 in 200 |
Classified as stillbirth rather than miscarriage in most jurisdictions |
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Around 10 to 20 percent of clinically recognized pregnancies end in miscarriage, with most estimates centering near 15%. The weekly hazard is front-loaded: roughly 80% of losses occur in the first trimester, and once a fetal heartbeat is confirmed around week eight the per-pregnancy risk drops to about 5%. By the second trimester, only 1-2% of recognized pregnancies are still at risk. The comparison that sticks: miscarriage is roughly twice as common as appendicitis over a lifetime, yet a national survey found most Americans believed it happened in fewer than one in twenty pregnancies.
The perception gap runs in the opposite direction from most entries on this site. Miscarriage is not overestimated but underestimated — a majority of respondents in the Bardos et al. survey placed the rate at 5% or lower. The silence around pregnancy loss feeds the misconception: when few people talk about it, each person who experiences it assumes they are an outlier. That assumption, in turn, generates guilt and isolation that the survey data quantifies plainly.
The headline number hides enormous heterogeneity by age. At 25 the per-pregnancy risk is about 10%; at 35 it is roughly 20%; by 40 it approaches 40%. Prior miscarriage history compounds the effect. And the 10-20% figure excludes biochemical pregnancies — very early losses before clinical detection — which would roughly double the total rate. If any of these factors apply, the population average is not your number.
Related tidbits
About 1 in 6 couples experience infertility (17.5%). Miscarriage affects roughly 20% of recognized pregnancies. Both are far more common than most people realize, and both remain under-discussed.
Claim ledger
Every number below is what each source reported, with the verbatim quote we relied on and how we arrived at our figure. Click any link to verify directly.
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[1] Birth Defects Research Part A: Clinical and Molecular Teratology — A systematic review to calculate background miscarriage rates using life table analysis
A systematic review to calculate background miscarriage rates using life table analysis- 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%)." ”
- Source data from
- 2012-06-01
- Accessed
- 2026-04-11 · archived copy
- Calculation
- 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.
- Independence
- 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.
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[2] BMJ — Role of maternal age and pregnancy history in risk of miscarriage: prospective register based study
Role of maternal age and pregnancy history in risk of miscarriage: prospective register based study- 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." ”
- Source data from
- 2019-03-20
- Accessed
- 2026-04-11 · archived copy
- Calculation
- 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.
- Independence
- Norwegian registry data is independent of the Ammon Avalos systematic review, which drew primarily from US and European cohort studies.
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[3] Obstetrics & Gynecology — A National Survey on Public Perceptions of Miscarriage
A National Survey on Public Perceptions of Miscarriage- 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" ”
- Source data from
- 2015-06-01
- Accessed
- 2026-04-11 · archived copy
- Calculation
- 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%.
- Independence
- Public-perception survey data, entirely separate from the epidemiological sources. Used only for the perceived-risk axis; does not feed into the probability estimate.
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[4] March of Dimes — Miscarriage
Miscarriage- 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." ”
- Source data from
- 2024-10-01
- Accessed
- 2026-04-11 · archived copy
- Calculation
- Patient-facing summary consistent with ACOG guidance and the Ammon Avalos systematic review. Used as corroborating reputable reference for the 10-20% headline range.
- Independence
- March of Dimes cites ACOG and underlying literature, so this is a dependent summary rather than an independent data source.