Vassard D, et al. - Researchers examined how hormone stimulation during assisted reproductive technology (ART) treatment affects the risk of ovarian cancer. They assessed data of women undergoing ART treatment during 1994–2015 registered in the Danish IVF register and linked the data with data from the Danish Cancer Register and socio-demographic population registers using an individual person identification number assigned to people residing in Denmark. They assessed the population sample consisting of 58,472 ART-treated women and 625,330 untreated women, all with no previous malignancies. During mean follow-up period of 9.7 years), 393 (0.06%) women were diagnosed with ovarian cancer. The analysis revealed that the risk of ovarian cancer in not higher among ART-treated women, with the exception of ART-treated women with endometriosis.