Vitamin D deficiency in women with polycystic ovary syndrome (PCOS) who have undergone fertility treatment with ovarian stimulation is associated with a significantly diminished rate of ovulation and pregnancy, and a lower chance of a live birth, according to findings published in the Journal of Clinical Endocrinology & Metabolism.
Growing evidence suggests that vitamin D plays an important role in human reproduction. Researchers hypothesized that vitamin D deficiency is a modifiable contributor to reduced treatment success in patients with PCOS or who have unexplained infertility, and who are undergoing ovarian stimulation. To test this hypothesis, vitamin D status was evaluated in stored samples from completed randomized controlled trials conducted by the Reproductive Medicine Network.
The cohort included participants from the Pregnancy in PCOS II randomized controlled trial (n=607) and the Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation (AMIGOS) randomized controlled trial of unexplained infertility (n=647). Serum 25(OH)D levels were measured using the banked sera samples. Investigators found that women deficient in vitamin D (25[OH]D <20 ng/mL or 50 nmol/L) were less likely to ovulate (adjusted odds ratio [aOR] 0.82; 95% CI, 0.68-0.99; P =.04) and had a 40% lower chance of live birth (aOR 0.63; 95% CI, 0.41-0.98; P =.04) vs those with normal vitamin D levels.
In the AMIGOS study, a significant association between vitamin D deficiency and live birth was not observed, but in pregnant women from both studies, vitamin D deficiency was associated with a higher risk for early pregnancy loss (OR, 1.6; 95% CI, 1.0-2.6; P =.05).
Investigators observed that vitamin D deficiency in women with PCOS who underwent ovarian stimulation was associated with significantly diminished rates of ovulation vs women with unexplained infertility, who did not have an association.
“Considering the prevalence of PCOS and vitamin D deficiency alongside the vast number of unsuccessful ovarian stimulation cycles conducted in this country every year, these results are pertinent to the reproductive outcomes of a substantial number of infertile women,” wrote the authors.
Reference
Butts SF, Seifer DB, Koelper N, et al. Eunice Kennedy Shriver National Institute of Child Health and Human Development Reproductive Medicine Network. Vitamin D deficiency is associated with poor ovarian stimulation outcome in PCOS but not unexplained infertility [published online August 3, 2018]. J Clin Endocrinol Metab. doi: 10.1210/jc.2018-00750