Cozzolino M, Busnelli A, Pellegrini L, et al. - Researchers conducted a systematic review and meta-analysis with the aim to determine the influence of serum vitamin D level on in vitro fertilization (IVF) outcomes. They systematically searched PubMed, MEDLINE, EMBASE, Global Health, The Cochrane Library, Health Technology Assessment Database, and Web of Science from inception until July 2019 and performed cross-checking of references from relevant articles in English. Categorization of Vitamin D levels into three groups was performed: deficient (< 20 ng/mL), insufficient (20−30 ng/mL), and replete (> 30 ng/mL). Findings suggest no influence of serum vitamin D levels on IVF outcomes in terms of clinical pregnancy rate, live birth rate, and/or ongoing pregnancy rate, and miscarriage rate. Currently, a lack of consensus was observed between the appropriate vitamin D threshold to prognosticate reproductive outcomes compared with the one established for bone health.