What are the odds a woman will develop endometriosis?
Evidence quality 4.25/5
Eight-dimension review score against the quality rubric . Each dimension scored 1–5.
- D1 Source grounding
- 3/5
- D2 Source authority
- 4/5
- D3 Arithmetic
- 5/5
- D4 Uncertainty
- 4/5
- D5 Scope
- 5/5
- D6 Prose
- 5/5
- D7 Perception honesty
- 4/5
- D8 Caveat completeness
- 4/5
Lifetime probability · lifetime, subgroup
1 in 10
10% lifetime chance
Most people underestimate this.
range 1 in 17 to 1 in 6.7
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≈ As likely as
Perceived
Endometriosis is simultaneously one of the most common gynecological conditions and one of the least intuitively understood in terms of its prevalence. Most adults cannot name a prevalence figure; those who can tend to significantly underestimate it. The condition's long diagnostic delay — averaging 7 to 11 years depending on the country — means that many women live with it for years before the word "endometriosis" ever appears in their medical record, which suppresses both public awareness and official prevalence figures. Surveys of women with endometriosis consistently report that they visited multiple providers before receiving a diagnosis, reinforcing a perception that the condition is rare when it is in fact common.
Rough estimate: Most adults have no clear prevalence estimate; those aware of the condition tend to guess lower than reality
Source: editorial intuition, not polled
Actual
~1 in 10 reproductive-age women worldwide
reproductive-age women, global
Show derivation
WHO estimates that endometriosis affects roughly 10% of reproductive-age women worldwide (~190 million). ACOG concurs with a ~1 in 10 figure for US women of reproductive age. A US National Survey of Family Growth (2011-2019) found a national self-reported prevalence of 6.4%, but this is widely considered an undercount because diagnosis requires either laparoscopy or advanced imaging, and many cases go undiagnosed for years. The true lifetime prevalence among women who live through their full reproductive years is likely closer to the 10% WHO figure, which is used here. Uncertainty band spans from the NSFG survey-based estimate (~0.06) to higher estimates from surgical series (~0.15) that include incidental findings in asymptomatic women undergoing surgery for other reasons.
Caveats: Endometriosis prevalence figures are inherently uncertain because definitive dia…
Endometriosis prevalence figures are inherently uncertain because definitive diagnosis historically required laparoscopic surgery, and many affected women never receive a diagnosis. The WHO/ACOG 10% figure is a consensus estimate that attempts to account for undiagnosed cases, but the true figure could be meaningfully higher or lower. The 7-11 year average diagnostic delay is one of the longest of any common medical condition, which means that point-in-time prevalence studies systematically undercount. This entry uses the prevalence figure (proportion of women who will have the condition at some point) rather than an annual incidence rate, because endometriosis is a chronic condition that does not have a clean "event per year" structure.
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Endometriosis affects roughly 1 in 10 women of reproductive age, according to both the World Health Organization (~190 million globally) and the American College of Obstetricians and Gynecologists. That makes it one of the most common gynecological conditions in the world — and one of the most consistently underestimated in casual conversation. The condition involves tissue similar to the uterine lining growing outside the uterus, causing chronic pain, heavy periods, and in many cases subfertility. A US National Survey of Family Growth (2011-2019) found a self-reported prevalence of 6.4%, but this is widely regarded as an undercount because diagnosis has historically required surgery, and many women live with symptoms for years before the word “endometriosis” ever enters their medical record.
The diagnostic delay is the defining structural problem. Across studies, the average time from symptom onset to diagnosis ranges from 7 to 11 years depending on the country. In the UK, 58% of women reported making multiple visits to their care provider before any investigation for endometriosis was undertaken. A 2025 systematic review confirmed that the delay is not shrinking appreciably despite increased awareness. The reasons are partly clinical — symptoms overlap with irritable bowel syndrome, urinary tract infections, and “normal” menstrual pain — and partly cultural: menstrual pain has historically been normalized in clinical settings, and many women report being told their symptoms were psychological before eventually receiving a diagnosis.
Endometriosis is not evenly distributed across the population. Women with a first-degree relative who has the condition face roughly five to seven times the baseline risk. Prevalence among women presenting with subfertility reaches 50-70% in surgical series, though this partly reflects diagnostic selection bias (women who undergo surgery are more likely to have their endometriosis found). Early menarche and shorter menstrual cycles are associated with modestly higher risk, while multiparity and breastfeeding appear protective — consistent with the hypothesis that cumulative menstrual exposure matters. The honest summary: this is a common, underdiagnosed, and undertreated condition whose public profile is finally beginning to match its epidemiological footprint.
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] World Health Organization — Endometriosis — fact sheet
Endometriosis — fact sheet- Statistic
Endometriosis affects roughly 10% (190 million) of reproductive-age women and girls globally- Excerpt
“"Endometriosis affects roughly 10% (190 million) of reproductive age women and girls globally. [...] There is currently no known way to prevent endometriosis. Enhanced awareness, followed by early diagnosis and management, may slow or halt the natural progression of the disease." ”
- Source data from
- 2025-03-28
- Accessed
- 2026-04-24 · archived copy
- Calculation
- WHO gives the headline 10% figure directly. This is a prevalence estimate, not incidence, and covers women of reproductive age (~15-49). It is based on a synthesis of epidemiological studies and is the most widely cited global figure. The denominator is all reproductive-age women, not just those who have undergone diagnostic surgery, so it implicitly includes estimated undiagnosed cases.
- Independence
- WHO synthesises multiple epidemiological studies into a consensus prevalence figure. Methodologically distinct from the ACOG clinical guidance below, though both draw on overlapping literature.
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[2] American College of Obstetricians and Gynecologists — Endometriosis
Endometriosis- Statistic
Endometriosis occurs in about 1 in 10 women of reproductive age- Excerpt
“"Endometriosis occurs in about 1 in 10 women of reproductive age. [...] Endometriosis is most often diagnosed in women in their 30s and 40s." ”
- Source data from
- 2024-12-01
- Accessed
- 2026-04-24 · archived copy
- Calculation
- ACOG's 1-in-10 figure aligns with the WHO consensus. ACOG notes that prevalence is much higher among women with subfertility or chronic pelvic pain, but the headline figure refers to the general population of reproductive-age women. Average diagnosis delay of 7-11 years means that cross-sectional prevalence studies undercount true lifetime prevalence.
- Independence
- ACOG is a US clinical-guidance body that synthesises peer-reviewed literature independently of WHO, though both draw on many of the same underlying studies.