International Doctorate School in Clinical and Experimental Medicine, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Italy.
Unit of Obstetrics and Gynecology, Mother-Infant Department, University of Modena and Reggio Emilia, Italy.
Int J Vitam Nutr Res. 2022 Mar;92(2):126-133. doi: 10.1024/0300-9831/a000691. Epub 2020 Dec 7.
Vitamin D is a secosteroid hormone that plays a pivotal role in several metabolic and reproductive pathways in humans. Increasing evidence supports the role of vitamin D deficiency in metabolic disturbances and infertility in women with polycystic ovary syndrome (PCOS). Indeed, supplementation with vitamin D seems to have a beneficial role on insulin resistance (IR) and endometrial receptivity. On the other hand, exceedingly high levels of vitamin D appear to play a detrimental role on oocytes development and embryo quality. In the current review, we summarize the available evidence about the topic, aiming to suggest the best supplementation strategy in women with PCOS or, more generally, in those with metabolic disturbances and infertility. Based on the retrieved data, vitamin D seems to have a beneficial role on IR, insulin sensitivity and endometrial receptivity, but high levels and incorrect timing of administration seem to have a detrimental role on oocytes development and embryo quality. Therefore, we encourage a low dose supplementation (400-800 IU/day) particularly in vitamin D deficient women that present metabolic disturbances like PCOS. As far as the reproductive health, we advise vitamin D supplementation in selected populations, only during specific moments of the ovarian cycle, to support the luteal phase. However, ambiguities about dosage and timing of the supplementation still emerge from the clinical studies published to date and further studies are required.
维生素 D 是一种固醇类激素，在人类的几种代谢和生殖途径中起着关键作用。越来越多的证据支持维生素 D 缺乏在多囊卵巢综合征（PCOS）妇女的代谢紊乱和不孕中的作用。事实上，维生素 D 的补充似乎对胰岛素抵抗（IR）和子宫内膜容受性有有益的作用。另一方面，极高水平的维生素 D 似乎对卵母细胞发育和胚胎质量起着有害的作用。在本综述中，我们总结了有关这一主题的现有证据，旨在为 PCOS 妇女或更普遍存在代谢紊乱和不孕的妇女提出最佳的补充策略。根据检索到的数据，维生素 D 似乎对 IR、胰岛素敏感性和子宫内膜容受性有有益的作用，但高水平和不正确的给药时间似乎对卵母细胞发育和胚胎质量有有害的作用。因此，我们鼓励低剂量补充（400-800 IU/天），特别是在存在代谢紊乱（如 PCOS）的维生素 D 缺乏的妇女中。至于生殖健康，我们建议在特定人群中补充维生素 D，仅在卵巢周期的特定时刻补充，以支持黄体期。然而，迄今为止发表的临床研究仍存在关于补充剂量和时间的问题，需要进一步研究。
