Overweight and obese anovulatory patients with polycystic ovaries: parallel improvements in anthropometric indices, ovarian physiology and fertility rate induced by diet

Background: This prospective study evaluated the effect of weight reduction on anthropometric indices and ovarian morphology in anovulatory overweight patients with polycystic ovary syndrome (PCOS). Methods: Thirty-three anovulatory overweight patients with PCOS were enrolled in the study. All had patent Fallopian tubes and chronic anovulation: 27 of them were oligo-amenorrhoeic. The partners were normospermic. Patients were prescribed a 1200 kcal/day diet, and physical exercise was recommended. Anthropometric indices and ovarian imaging parameters were assessed at baseline and after weight loss of 5 and 10%. Results: Twenty-five patients (76%) lost at least 5% of their body weight. Eleven of these patients (33%) reached a 10% decrease in weight. Waist circumference at the umbilical level, hip circumference, four skin folds, body mass index and fatty mass ratio were significantly reduced after 5 and 10% weight loss. Ovarian morphology changed during the diet: we observed a significant reduction in ovarian volume and in the number of microfollicles per ovary. Among the 27 patients with oligo-amenorrhoea, 18 had a resumption of regular cycles and 15 experienced spontaneous ovulation; 10 spontaneous pregnancies occurred in patients who lost at least 5% of their weight. Conclusions: Weight loss through a controlled low-calorie diet improves anthropometric indices in obese PCOS patients, reduces ovarian volume and microfollicle number and can restore ovulatory cycles, allowing spontaneous pregnancy.