Follicular fluid 25-hydroxyvitamin D levels determine fertility outcome in patients with polycystic ovary syndrome

Abstract

Objective: To determine the possible relationship between follicular fluid 25-hydroxyvitamin D [25(OH)D] levels and fertility outcome of women who underwent IVF/ICSI with the diagnosis of lean polycystic ovary syndrome.

Materials and methods: Thirty patients who were diagnosed with PCOS according to the Rotterdam criteria and decided on IVF/ICSI were included in the study. Thirty patients who were scheduled for IVF/ICSI for reasons other than PCOS and matched in terms of age and BMI were taken as the control group (non-PCOS). According to BMI values, patients in both PCOS and non-PCOS groups were lean. Women in both groups were aged 21-35 years with a normal BMI (18.5-24.9 kg/m2) and first IVF/ICSI attempt. Both groups of patients were followed up using the antagonist protocol. Vit D levels were measured in serum and follicular fluid (FF) samples taken on the day of oocyte collection. The correlation between FF vit D levels, the number of total oocytes, MII oocytes and 2 PN zygotes, HOMA-IR, hormonal and demographic parameters, clinical pregnancy rate (CPR), live birth rate (LBR), and miscarriage rate were evaluated.

Results: At the time of oocyte retrieval women with PCOS had similar serum Vitamin D compared to non-PCOS women (21.8 (12.6-24.8) ng/ml vs 22.3 (11.5-25.1) ng/ml, p < 0.54). In FF, assessed on the day of oocyte retrieval, the concentration of Vitamin D was similar in women with PCOS when compared to non-PCOS women (11.2 (9.2-14.4) ng/ml vs 13.3 (11.1-17.4) ng/ml, p < 0.06). For both groups, Vitamin D levels were lower in FF compared to serum vit D. A positive correlation was found between serum and FF Vitamin D concentrations in the full cohort. A positive and significant correlation was found between FF-vit D levels and the number of total oocyte (r = 0.344, p < 0.04) and MII oocyte (r = 0.404, p < 0.02) in the PCOS group. The number of total oocyte, MII oocyte and 2 PN zygotes of the PCOS group were significantly higher than the non-PCOS group. Positive pregnancy test rate, clinical pregnancy and live birth rates were similar in both groups. The miscarriage rates in the non-PCOS group were significantly higher than in the PCOS group. A positive and significant correlation was also found between FF vit D levels and positive pregnancy test (r = 0.566, p < 0.03) and CPR (r = 0.605, p < 0.02) in PCOS group. There was no correlation between FF-vit D levels and live birth and miscarriage rates in neither the PCOS nor the non-PCOS group.

Conclusions: Both serum and FF 25-hydroxyvitamin D level of women with PCOS at the time of oocyte retrieval are similar to non-PCOS controls. While FF 25-hydroxyvitamin D levels correlate with total and MII oocyte counts, positive pregnancy test and CPR, it does not correlate with miscarriage and live birth rates.

Keywords: 25-Hydroxyvitamin D; Clinical pregnancy; Follicular fluid; Live birth; Miscarriage; PCOS.