Received July 02, 2023
Accepted December 02, 2023

Objective: Vitamin D (VD) is a fat-soluble steroid hormone, synthesized by the skin, most known for its role in bone mineral balance. Vitamin D receptors (VDR) are also found in the female reproductive system, but their role remains unclear. The objective of this study was analyze the relationship between serum vitamin D levels and the number of oocytes retrieved after ovarian stimulation. Methods: This is a retrospective study of 267 patients undergoing in vitro fertilization (IVF) conducted in the Fertipraxis clinic, a private practice facility. Patients were initially divided into two groups according to their VD levels. Group 1 included 152 patients with VD levels < 30 ng/mL and group 2 represented 115 patients with VD levels > 30 ng/mL. They were further analyzed and separated considering their age, anthropometric data, ovarian reserve, amount of gonadotropin used, and follicles obtained until trigger day. Results: In the presented analysis, no difference was found in the number of follicles and oocytes retrieved as well as in the number of mature oocytes obtained from patients with both vitamin D deficiency and sufficiency. Conclusion: The results of our study show no difference among number of follicles, oocytes retrieved, and mature oocytes obtained after ovarian stimulation according to their vitamin D serum levels. Further higher quality studies are needed to evaluate the possible roles of serum vitamin D levels in other stages of human fertilization process.