The effect of low dose human chorionic gonadotropin on follicular response and oocyte maturation in PCOS patients undergoing IVF cycles: a randomized clinical trial of efficacy and safety.

Purpose: To compare the efficacy of two regimens of low dose human chorionic gonadotropin (hCG) on follicular response and oocyte maturation in women with polycystic ovarian syndrome (PCOS).

Methods: Ninety women with PCOS who underwent assisted reproduction were eligible for this controlled, prospective, randomized study. Our trial was performed at Royan Institute Reproductive Research Center over a 24-month period. Ovarian stimulation in all groups was initiated with recombinant FSH, 150 IU daily. The dose and duration of FSH treatment were adjusted by monitoring follicular development with ultrasound and estradiol levels. Patients were randomized using a block randomization technique which assigned them to three groups: group A (control group) continued r-FSH until oocyte retrieval. In group B, r-FSH was reduced to 75 IU once the lead follicle reached 14 mm in mean diameter and low dose hCG (100 IU/day) was initiated. In group C, r-FSH was discontinued and low dose hCG (200 IU/day) was begun when the lead follicle reached 14 mm in mean diameter. The main outcome measure was follicular response and oocyte maturation.

Results: As compared to the FSH only group, groups which were given low dose hCG had lower gonadotropin consumption and fewer immature oocytes than the control group. No women in the low dose hCG groups developed severe ovarian hyper-stimulation syndrome. Fertilization, implantation and pregnancy rates were similar in the three groups.

Conclusions: A combination of FSH and low dose hCG improved oocyte maturity and preserved outcomes with improved safety and lowered cost.