Serum Levels of 25-Hydroxyvitamin D and Time to Natural Pregnancy

Aim: The aim of this study was to evaluate whether natural fertility is related to serum 25-hydroxyvitamin D (25-OH-vitamin D) levels. Methods: A nested case-control study was designed from a prospective cohort of pregnant women undergoing first trimester screening for aneuploidies. Cases included women seeking pregnancy for 12-24 months. Controls were the subsequent age-matched women conceiving in less than 1 year. We excluded women aged ≥40 or Results: Seventy-three cases and 73 matched controls were selected. The mean ± SD serum 25-OH-vitamin D was 21.2 ± 6.8 and 19.7 ± 7.3 ng/ml, respectively (p = 0.16). The number (%) of women with serum levels Conclusions: Our study does not support a crucial role of 25-OH-vitamin D in natural fertility.