Vitamin D affects estrogen level by stimulating the synthesis of testosterone, estrogen and progesterone. Insufficiency of vitamin D leads to a decrease in the values of these steroid hormones. The average value of 25 (OH) D was 26.95 ± 16.6 ng/ml, which indicates insufficiency. The median estradiol was 47.85 pg/ml, which is below the reference values during the follicular phase. Vitamin D deficiency in this sample may be one of the reasons. Prophylactic vitamin D and calcium supplementation will contribute to the improvement of this situation.