A Comparison of the Effects of Early and Late Ovarian Stimulation on Reproductive Outcomes in Patients with Polycystic Ovary Syndrome

BACKGROUND/AIMS: Data on the effect of onset time of gonadotropins for ovarian stimulation on in vitro fertilization (IVF) outcomes are limited. This study was planned to compare the effects of early and late-onset ovarian stimulation on gonadotropin dose, ongoing pregnancy and live birth rates in women with polycystic ovary syndrome (PCOS).MATERIALS AND METHODS: The data of 432 patients who underwent IVF/intracytoplasmic sperm injection for PCOS-induced infertility/ subfertility were reviewed retrospectively. Among them, 304 were included in this study. They were divided into two groups according to the timing of their ovarian stimulation (2nd & 5th days of the menstrual cycle).RESULTS: The total oocyte count, the number of fertilized oocytes, and the number of grade 1 or 2 embryos were significantly higher in those subjects receiving ovarian stimulation on the 2nd day of the menstrual cycle. Those patients who received ovarian stimulation on day 2 had a higher total gonadotropin dose and a longer gonadotropin administration time. Although the number of total oocytes was higher in those patients starting treatment on the 2nd day, treatment started on day 5 (shorter treatment) provided better fertilization.CONCLUSION: In women with infertile PCOS, ovarian stimulation started on the 2nd day of the cycle provided more favorable IVF results in terms of total oocytes and fertilized oocytes, while the total gonadotropin dose was found to be higher. Fertilization and oocyte quality were better in the stimulations started on the 5th day.