Vitamin D Supplementation Improves Follicle Maturation By Regulating Oxidant/Antioxidant Balance in Women With PCOS

Objective: To investigate the effect of vitamin D (VD) supplementation on follicular fluid total oxidant status (TOS) and total antioxidant status (TAS) in women undergoing IVF/ICSI due to PCOS. Materials and Methods: Forty infertile women who were diagnosed with PCOS and decided on IVF/ICSI and whose serum VD levels were lower than 20 ng/mL were included in the study. The VD levels of the patients were determined according to the proposal of Endocrine Society. The patients were divided into two equal groups with 20 patients in each group. While the patients in Group 1 were given 400 IU/day of oral VD3 replacement, the patients in Group 2 were given 600 IU/day of oral VD3. VD treatment was started one month before the controlled ovarian stimulation cycle and continued throughout the following cycle. Fifteen patients with serum VD levels >30 ng/mL were taken as the control group. Oral VD replacement was not given to the patients in the control group. TAS and TOS values were measured in the follicle fluids taken from the patients in the VD replacement group and the patients in the control group on the day of ooist pick-up. Results: When compared with the control group, the follicular fluid TAS levels of both groups with VD replacement were significantly higher, while TOS levels were found to be significantly lower. When 400 IU/day VD replacement and 600 IU/day VD replacement were compared within themselves, follicular fluid TAS and TOS levels were found to be similar. Increasing the VD replacement dose from 400 IU/day to 600 IU/day did not cause a significant change in TAS and TOS values. A positive and significant correlation was found between intrafollicular TAS levels and serum VD, MII oocyte, 2PN zygote and clinical pregnancy rates. A negative correlation was found between intrafollicular TOS levels and serum VD, 2PN zygote and clinical pregnancy rates. Conclusions: VD replacement therapy contributes to follicle maturation by regulating intrafollicular oxidant/ antioxidant balance in PCOS patients.