Fertility in patients with untreated rectosigmoid endometriosis

•The total pregnancy rate of the study population was 48%.•29% of the women had a live birth after natural conception.•The median time required to conceive naturally was 10 months.•16% of the women had a live birth after conceiving by ART.•A worsening of pain and intestinal symptoms were observed in case of multiple IVF. Several studies have investigated reproductive outcomes following surgical treatment of colorectal endometriosis, mainly segmental colorectal resection. This study examines pregnancy and live birth rates of women with rectosigmoid endometriosis not treated by surgery. A retrospective analysis of data collected between May 2009 and January 2020 related to 215 women affected by rectosigmoid endometriosis wishing to conceive. Patients had a diagnosis of rectosigmoid endometriosis by transvaginal ultrasonography and magnetic resonance imaging enema. Patients with estimated bowel stenosis >70% at computed tomographic colonography and/or subocclusive/occlusive symptoms were excluded. During the median length of follow-up of 31 months (range 13–63 months), the total pregnancy and live birth rates of the study population were 47.9% and 45.1%, respectively. Sixty-two women had a live birth after natural conception (28.8%; 95% confidence interval [CI] 22.8–35.6%) with a median time required to conceive of 10 months (range 2–34 months). Eighty-three women underwent infertility treatments (38.6%, 95% CI 32.1–45.5%); among these, 68 patients underwent IVF either directly (n = 51) or after intrauterine insemination (IUI) failure (n = 17). Time to conception was significantly higher in women having conceived by IVF than in those having conceived naturally (P