Long-Term Risk of Ovarian Cancer and Borderline Tumors After Assisted Reproductive Technology.

Background: Long-term effects of assisted reproductive technology (ART) on ovarian tumor risk are unknown.

Methods: This nationwide cohort study comprises 30 625 women who received ovarian stimulation for ART in 1983-2000 and 9988 subfertile women not treated with ART. Incident invasive and borderline ovarian tumors were ascertained through linkage with the Netherlands Cancer Registry and the Dutch Pathology Registry until July 2018.