Vitamin D, PCOS and androgens in men: a systematic review

Abstract

BackgroundAccumulating evidence from animal and human studies suggests that vitamin D is involved in many functions of the reproductive system in both genders.AimThe aim of this review was to provide an overview on the effects of vitamin D on polycystic ovary syndrome (PCOS) in women and androgen metabolism in men.MethodsWe performed a systematic literature search in PubMed for relevant English language publications published from January 2012 until September 2017.Results and discussionThe vitamin D receptor and vitamin D-metabolizing enzymes are found in reproductive tissues of women and men. In women, vitamin D status has been associated with several features of PCOS. In detail, cross-sectional data suggest a regulatory role of vitamin D in PCOS-related aspects such as ovulatory dysfunction, insulin resistance as well as hyperandrogenism. Moreover, results from randomized controlled trials (RCTs) suggest that vitamin D supplementation may be beneficial for metabolic, endocrine and fertility aspects in PCOS. In men, vitamin D status has been associated with androgen levels and hypogonadism. Further, there is some evidence for a favorable effect of vitamin D supplementation on testosterone concentrations, although others failed to show a significant effect on testosterone levels.ConclusionIn summary, vitamin D deficiency is associated with adverse fertility outcomes including PCOS and hypogonadism, but the evidence is insufficient to establish causality. High-quality RCTs are needed to further evaluate the effects of vitamin D supplementation in PCOS women as well as on androgen levels in men.

The effect of vitamin D supplementation on the androgenic profile in men: A systematic review and meta‐analysis of clinical trials

“…In term of intervention, treatment duration (<16 or ≥16 weeks), type of prescription (weekly or daily), daily doses of vitamin D supplementation (<3,000 IU/day or ≥ 3,000 IU/day) and baseline 25(OH)D and TT levels confirmed the null finding in total analysis. Our results are consistent with the current systematic review (Trummer et al, ), which found conflicting results about the effect of vitamin D supplementation on TT in men in RCTs and observational studies. The most observational studies in this systematic review found an independent association between vitamin D and TT.…”

The Role of Vitamin D in Fertility and during Pregnancy and Lactation: A Review of Clinical Data

“…Prevention of rickets and thus avoiding narrowing of the pelvis with obstructive childbirth might be a hypothetical explanation for the advantage of having a light skin. Apart from this, several studies and reviews have highlighted the potential role of vitamin D for female fertility today [ 45 , 46 , 47 , 48 , 49 , 50 , 51 ]. Interestingly, in northern countries there is a seasonal variation in pregnancy rates with a peak in summer and autumn, i.e., the seasons with the highest serum 25(OH)D concentrations [ 46 ].…”

Effect of vitamin�D supplementation on polycystic ovary syndrome: A meta‑analysis

“…Recently, a series of studies have demonstrated that vitamin D deficiency (VDD) is common in patients with PCOS and that VDD may be associated with metabolic and endocrine disorders in PCOS (4)(5)(6)(7). Compared with the general population, the prevalence of VDD is relatively higher in PCOS patients (6).…”