The Effects of Follicular Fluid 25(OH)D Concentration on Intrafollicular Estradiol Level, Oocyte Quality, and Fertilization Rate in Women Who Underwent IVF Program.

Objective: 25(OH)D (Vitamin D) has been investigated for its role in the process of folliculogenesis and thus affects the quality of oocyte produced by in vitro fertilization. Our aims were to investigate the effects of 25(OH)D levels in follicular fluid, follicular estradiol level, successful fertilization rate in IVF treatment and the correlation between 25(OH)D levels in follicular fluid with the oocyte quality. Design and Setting: This is an analytic observational study with cross-sectional design conducted between September-November 2018 in two fertility clinics at tertiary hospitals in Bandung, Indonesia. Participants: The inclusion criteria were women aged 20-35 years who underwent controlled ovarian stimulation in IVF program with normal ovarian reserve and normal BMI. Eligible women were divided into two groups based on their 25(OH)D levels: low and high.
Results: There was a significant difference in oocyte quality (p = 0.03) and follicular estradiol levels (p = 0.02) between the two categories of 25(OH)D levels. High level of 25(OH)D has significantly higher level in comparison with the low level of 25(OH)D. No significant differences were found in terms of successful fertilization rate (p = 0.13). High level of 25(OH)D has higher successful fertilization rate compared to low level of 25(OH)D (71.8% vs 55.26%). A significant positive correlation between 25(OH)D level in follicular fluid and oocyte quality was also found (r = 0.32, p = 0.01).
Conclusion: Women with higher level of 25(OH)D are significantly more likely to have high-quality oocyte and follicular estradiol levels than those with low level of 25(OH)D, although there are no significant results for its relation to successful fertilization rate. © Federation of Obstetric & Gynecological Societies of India 2022.