Women who underwent ovarian stimulation for assisted reproductive technology were more likely to develop ovarian cancer, compared with the general population but not compared with subfertile women who didn't receive ART, with increased parity and successful ART cycles associated with reduced ovarian cancer risk, while ART also correlated with elevated borderline ovarian tumor risk, according to a study in the Journal of the National Cancer Institute. "The higher risk of ovarian cancer compared with the general population is likely due to the higher prevalence of nulliparity in ART-treated women," researchers wrote.