The Role of Vitamin D Supplementation Program on Fertility Outcomes in Women with Embryo Transfers

Objective: This study aimed to determine the effect of vitamin D supplementation given to women undergoing embryo transfer on pregnancy outcomes. Materials and Methods: This study was conducted experimentally in a pre-test-post-test design. The sample of the study consisted of a total of 118 women, with 58 in the intervention group and 60 in the control group. While the vitamin D supplementation program was administered to women in the intervention group at the beginning of infertility treatment, women in the control group did not receive a vitamin D supplementation program. At the end of the study, pregnancy and clinical pregnancy rates of women in the intervention and control groups, as well as their serum 25(OH) D levels, were examined. Results: The vitamin D level of women in the intervention group at the beginning of treatment (12.47±6.03 ng/mL) was statistically significantly lower than the vitamin D level on the day of beta-hCG (32.34±9.62 ng/mL) (p=0.000). The mean vitamin D level of the women in the control group (14.30±7.03 ng/mL) on the day of beta-hCG was statistically significantly lower than that of the women in the intervention group (32.34±9.62 ng/mL) (p=0.000). While there was no statistically significant difference in the pregnancy rates of women in the intervention and control groups, a statistically significant difference was found in the clinical pregnancy rates (respectively, p=0.066 and p=0.014). Conclusion: This study demonstrated that vitamin D supplementation program for women undergoing infertility treatment with deficient or insufficient vitamin D levels may increase vitamin D levels and clinical pregnancy rate after embryo transfer.