Work

History of full-term delivery is associated with older age at first hospital diagnosis of endometriosis: A retrospective cohort study

Year: 2026

Type: article

Abstract: Current evidence does not support that pregnancy can cure or reduce endometriotic symptoms, although hormonal and immunological changes occur during pregnancy. However, given the opposing effects of these changes, it remains unclear whether the history of full-term delivery is associated with a later age at clinical diagnosis of endometriosis. Here, we investigated the association between the history of full-term delivery and the age at first in-hospital diagnosis. 1,910 women diagnosed with endometriosis were included. Age at first-hospital diagnosis was collected and compared between women with and without a history of full-term delivery. All parous women included in this study had a full-term delivery before their first in-hospital diagnosis. The mean age at first in-hospital diagnosis was 38 years (±7.2) in parous women, significantly older than in nulliparous women (30 years; p<0.0001). However, age at first in-hospital diagnosis in women with a history of full-term delivery did not differ by the number of full-term deliveries or by delivery mode. A significantly higher percentage of nulliparous women (82%) were diagnosed by age 35 years, compared to 37% of parous women (p<0.0001). Parous women showed a clear peak in endometriosis incidence between 36 and 45 years, with 45% diagnosed in this age group. Conversely, only 13.5% of nulliparous women were diagnosed in this age range (p<0.0001). Our study demonstrates a delay in in-hospital clinical diagnosis of endometriosis and a shifted peak incidence in women with a history of full-term delivery. Our study provides new insight into the association between a history of full-term delivery and the clinical diagnosis of endometriosis.

Source: AJOG Global Reports

DOI: 10.1016/j.xagr.2026.100715