Assisted reproductive technology pregnancy complications are significantly associated with endometriosis severity before conception: a retrospective cohort study.

Background Endometriosis has been shown to be associated with second- to third-trimester pregnancy complications such as preterm birth and placenta previa, but the evidence is inconsistent. We hypothesized that endometriosis severity might affect these inconsistent results. Therefore we aimed to conduct a retrospective cohort study to elucidate whether endometriosis severity is associated with the incidence rates of adverse pregnancy outcomes.