ObjectiveIt has been suggested that excess body weight could represent a risk factor for infertility outcomes. The present study aimed to evaluate the association of overweight and anovulation among infertile women with regular menstrual cycles.MethodsWe conducted a retrospective case-control study with consistently anovulatory patients undergoing assisted reproduction treatment. The patients were stratified into normal weight (body mass index [BMI]: 18.5–24.9kg/m2) and overweight (BMI: 25.0–29.9kg/m2).Those with polycystic ovary syndrome or obesity were excluded. The groups were matched for age, duration of infertility, prolactin, follicle stimulating hormone (FSH), thydroid stimulating hormone (TSH), luteinizing hormone (LH), and estradiol levels.ResultsOverweight was significantly associated with anovulation, when using the World Health Organization (WHO) criteria for anovulation: progesterone levels > 5.65 ng/ml and ultrasonography evidence of follicle collapse (odds ratio [OR]: 2.69; 95% confidence interval [CI95%]: 1.04–6.98).ConclusionBody mass index above the normal range jeopardizes ovulation among non-obese infertile women with regular menstrual cycles.