Correlation between 25-hydroxy vitamin D levels in women and in vitro fertilization outcomes: A cross-sectional study

BACKGROUND: Vitamin D has recently raised a great deal of controversy, not because of its traditional role of absorbing calcium and maintaining bone health, but because of its unconventional role as an endocrine factor and the extent of its impact when linked to its specific receptors (VDR) found in different tissues. Research has raced trying to find its different roles in those tissues and its association with different clinical or medical conditions, and among these cases, its role in reproductive functions and fertility in women, these studies conflicted between supporting and denying the role of vitamin D in reproductive function and rejecting this hypothesis according to the results of their study. MATERIALS AND METHODS: The in vitro fertilization process allowed us to study the possible hypotheses, as this technique provides an opportunity to study the relationship between vitamin D levels with the in vitro fertilization outcomes, thus providing us with an idea of the relationship of vitamin D with fertility in women. In order to study this relationship, we designed our research as a cross-sectional study to confirm or deny this claim. Vitamin D was measured in the blood and in the follicular fluid for all cases using the electrochemiluminescence immunoassay (ECLIA) for the assay of total vitamin D, then IVF outcomes were compared with the levels of vitamin D in the blood. RESULTS: the levels of vitamin D are not related to the criteria of eggs such as the number of eggs and the maturity rate (MR) of eggs, but they are correlated in a statistically significant manner with the fertility rate (FR), and at the same time the levels of vitamin D in the blood were completely independent of the clinical pregnancy rate (CPR). CONCLUSION: blood vitamin D levels will affect the FR when its levels in the blood drop below a specified value, vitamin D did not correlate with the CPR. In the long run, there is scope for more research projects on vitamin D. Future research could include case-control studies of patients on vitamin D supplementation, and the study of its correlation with IVF outcomes.