Hormone-free vs. follicle-stimulating hormone–primed infertility treatment of women with polycystic ovary syndrome using biphasic in vitro maturation: a randomized controlled trial

To compare oocyte maturation rates and pregnancy outcomes in women with polycystic ovary syndrome (PCOS) undergoing biphasic in vitro maturation (capacitation in vitro maturation [CAPA-IVM]) with vs. without follicle-stimulating hormone (FSH) priming. Randomized, controlled, assessor-blinded trial. Private hospital. Women aged 18–37 years with PCOS and an indication for CAPA-IVM. Participants were randomized (1:1) to undergo CAPA-IVM with or without FSH priming. The FSH priming group had 2 days of FSH injections before oocyte pickup; no FSH was given in the non-FSH group. After CAPA-IVM, day-5 embryos were vitrified for transfer in a subsequent cycle. The primary endpoint was number of matured oocytes. Secondary outcomes included rates of live birth, implantation, clinical pregnancy, ongoing pregnancy, pregnancy complications, obstetric and perinatal complications, and neonatal complications. The number (interquartile range) of matured oocytes did not differ significantly in the non-FSH vs. FSH group (13 [9–18] vs. 14 [7–18]; absolute difference –1 [95% confidence interval –5 to 4]); other oocyte and embryology outcomes did not differ between groups. Rates of ongoing pregnancy and live birth were 38.3% in the non-FSH group and 31.7% in the FSH group (risk ratio for both outcomes: 1.21, 95% confidence interval 0.74–1.98). Maternal complications were infrequent and occurred at a similar rate in the two groups; there were no preterm deliveries before 32 weeks gestation. These findings open the possibility of a new, hormone-free approach to infertility treatment of women with PCOS.