Objective: The peak number of oocytes is reached during intrauterine development, after which numbers decline until reserves are depleted and a woman enters menopause. In premature ovarian insufficiency (POI), the process of follicle depletion occurs at a young age (generally taken as 40 years); the condition affects about 1% of women. In this study, we investigate whether women with POI had experienced a different perinatal milieu, as reflected in their birth weight or prematurity. Study design: In this retrospective case-control study, we evaluated whether women diagnosed with POI had a different birth weight or prematurity rate (<37 weeks) compared with women aged over 40 at natural menopause (the controls). Binary logistic regression models were used to analyze the data and correct for smoking. 59 women with POI and 92 controls were recruited. Results: 13.6% of women diagnosed with POI were born prematurely, compared with 6.6% of controls (p = 0.018). Corrected for gestational age, women with POI did not have a different birth weight compared with controls. As a consequence of the design of our study, mean age at time of interview differed significantly between groups, at 37.5 and 46 years respectively for women diagnosed with POI and controls. Years of oral contraception use, smoking, age at menarche, BMI and education levels were similar in the two groups. Conclusion: Our findings indicate that prematurity is a risk factor for POI. Prenatal factors contributing to prematurity, or postnatal factors that are the result of prematurity, may lead to early follicle depletion. (C) 2016 Elsevier Ireland Ltd. All rights reserved.