Role of vitamin D in uterine fibroid biology

Objective: To provide a detailed summary of current scientific knowledge on uterine fibroids (leiomyomas) in vitro and in in vivo animal models, as well as to postulate the potential role of vitamin D3 as an effective, inexpensive, safe, long-term treatment option for uterine fibroids. Design: PubMed search articles were used to identify the most relevant studies on uterine fibroids, as well as effects of vitamin D3 on uterine fibroid cells and fibroid tumor growth in in vivo animal models. Setting: University research laboratory. Patient(s): Not applicable. Intervention(s): None. Main Outcome Measure(s): Not applicable. Result(s): Despite numerous publications available on uterine fibroids, information about the role that vitamin D3 plays in the regulation of uterine fibroids is limited. Most of the recent vitamin D3-related studies on uterine fibroids were published from our group. Recent studies have demonstrated that vitamin D deficiency plays a significant role in the development of uterine fibroids. Our recent studies have demonstrated that vitamin D3 reduces leiomyoma cell proliferation in vitro and leiomyoma tumor growth in in vivo animal models. These results postulate the potential role of vitamin D3 for an effective, safe, nonsurgical medical treatment option for uterine fibroids. Conclusion(s): This article reviews human and animal studies and uncovers new possibilities for understanding the vitamin D-based therapeutic option for an effective, safe, long-term treatment of uterine fibroids. On the basis of these results, a clinical trial with vitamin D3 or a hypocalcemic analog, paricalcitol, may be warranted for nonsurgical medical treatment of uterine fibroids. (C) 2015 by American Society for Reproductive Medicine.