Dural O, Kurbanova T, Yasa C, et al. - The underlying cause of primary ovarian insufficiency (POI) cannot be found in a significant number of affected women. Researchers here examined if anogenital distance (AGD), which is considered as a biomarker for prenatal hormonal environment, is associated with idiopathic POI in adolescents and young women. In this case control study, patients between the ages of 15-30, who developed POI following menarche without any identified genetic or iatrogenic cause comprised the study group and patients of the same age range who were having regular menstrual periods and were not diagnosed with polycystic ovary syndrome or endometriosis formed the control group. In total, 37 POI patients and 44 controls were assessed for distance between the anterior clitoral surface and the upper verge of the anus, and between the posterior fourchette and the upper verge of the anus. Results here yield the first evidence of a strong correlation between shorter AGD measurements and the presence of idiopathic POI indicating the possible role of prenatal environment in the development of POI.