Follicular and serum levels of vitamin D in women with unexplained infertility and their relationship with in vitro fertilization outcome: an observational pilot study.

Introduction Follicular and serum vitamin D are considered potential markers of the oocyte and embryos' quality and predictors of in vitro fertilization (IVF) outcomes. Methods This retrospective cross-sectional study correlated vitamin D in sera and follicular fluid of women with unexplained infertility mutually and with IVF outcomes. ELISA was used for measuring vitamin D. Results The results show positive correlation only between follicular and serum levels of vitamin D (Rho = 0.615, p = 0.025), and between follicular levels of vitamin D and the percentage of embryo fragmentation (Rho = 0.544; p = 0.036). Conclusions The results suggest that serum and follicular fluid vitamin D measurements could be complementary tools to the routine assessment of embryos.