Accumulating evidence from animal and human studies suggests that vitamin D is involved in many functions of the human reproductive system in both genders, but no comprehensive analysis of the potential relationship between vitamin D status and Assisted Reproduction Technologies (ART) outcomes is currently available. On this basis, the purpose of this systematic review and meta-analysis was to perform an in-depth evaluation of clinical studies assessing whether vitamin D status of patients undergoing ART could be related to cycle outcome variables. This issue is of interest considering that vitamin D deficiency is easily amenable to correction and oral vitamin D supplementation is cheap and without significant side effects. Surprisingly, no studies are currently available assessing vitamin D status among male partners of couples undergoing ART, while seven studies on vitamin D status of women undergoing controlled ovarian hyperstimulation (COH) for ART were found and included in the review. Results show that vitamin D deficiency is highly prevalent among women undergoing COH, ranging from 21% to 31% across studies conducted in Western countries and reaching 75-99% in Iranian studies. Data on vitamin D deficiency (25-hydroxyvitamin D serum levels <20 ng/ml) in relation to ART outcomes could be extracted from three studies and included in the meta-analysis, yielding a common risk ratio (RR) of 0.89 (95% CI 0.53-1.49) and showing a lower but not statistically significant likelihood of clinical pregnancy for vitamin-D-deficient women compared with vitamin-D-sufficient patients. In conclusion, there is insufficient evidence to support the routine assessment of vitamin D status to predict the clinical pregnancy rate in couples undergoing ART. The partly conflicting results of the available studies, potentially explaining the lack of statistical significance for a negative influence of vitamin D deficiency on clinical pregnancy rate, are likely secondary to confounders and insufficient sample size, and further larger cohort and randomised controlled studies are required.
Vitamin D and assisted reproduction Technologies : current concepts / V.S. Vanni, P. Vigano', E. Somigliana, E. Papaleo, A. Paffoni, L. Pagliardini, M. Candiani. - In: REPRODUCTIVE BIOLOGY AND ENDOCRINOLOGY. - ISSN 1477-7827. - 12:1(2014), pp. 47.1-47.11.
|Titolo:||Vitamin D and assisted reproduction Technologies : current concepts|
VIGANO', PAOLA (Corresponding)
CANDIANI, MASSIMO (Ultimo)
|Parole Chiave:||25-hydroxyvitamin D; Assisted reproduction technology (ART); Controlled ovarian hyperstimulation (COH); In vitro fertilization (IVF); Infertility; Meta-analysis; Vitamin D; Animals; Dietary Supplements; Female; Humans; Infertility, Female; Infertility, Male; Male; Nutritional Status; Pregnancy; Pregnancy Outcome; Pregnancy Rate; Prevalence; Reproducibility of Results; Semen Analysis; Vitamin D; Vitamin D Deficiency; Reproductive Techniques, Assisted; Developmental Biology; Endocrinology; Reproductive Medicine; Medicine (all)|
|Settore Scientifico Disciplinare:||Settore MED/40 - Ginecologia e Ostetricia|
|Data di pubblicazione:||2014|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1186/1477-7827-12-47|
|Appare nelle tipologie:||01 - Articolo su periodico|