Polyendocrine Metabolic Ovarian Syndrome (PMOS), previously known as Polycystic Ovarian Syndrome (or PCOS), is one of the leading causes of infertility worldwide and among the most common endocrine disorders affecting women of reproductive age. PMOS is estimated to impact up to 20% of women globally.
PMOS can impair fertility through several biological pathways. Research has shown that the condition contributes to hormonal imbalances, ovulatory dysfunction, chronic inflammation, metabolic disturbances, and cellular dysfunction – all of which can negatively affect reproductive health. PMOS is also closely associated with endometriosis, a highly inflammatory condition that can further compromise healthy reproduction and has been linked to infertility, miscarriage, and IVF failure.
Vitamin D deficiency is another major global health concern. More than one billion people worldwide are estimated to have insufficient vitamin D levels, representing nearly half of the global population.
A growing body of research suggests that vitamin D plays a critical role in reproductive health. Studies indicate that vitamin D supports ovarian follicle development, corpus luteum function, anti-Müllerian hormone (AMH) signaling, follicle-stimulating hormone (FSH) activity, and the production of progesterone, a hormone essential for successful reproduction.
Importantly, vitamin D deficiency has been strongly linked to PMOS, and studies suggest that up to 85% of women with PMOS are vitamin D deficient.
Numerous studies have identified associations between low vitamin D levels and both the development and severity of PMOS symptoms. Vitamin D, which is synthesized from cholesterol, is a prohormone that is converted by the body into an active hormone that promotes calcium metabolism and immune-system function. In women with PMOS, vitamin D deficiency has been associated with calcium dysregulation and follicular arrest, which may contribute to menstrual irregularities and reduced fertility.
It has been proposed that supplementation with vitamin D in women preparing for pregnancy, and those with PMOS, may be of benefit by providing protection against oxidative stress, and help maintain calcium levels within the cell, which in turn promotes healthy fertilization, cellular division, early-pregnancy implantation, and placental formation.
Given the importance of vitamin D in reproductive health and its close relationship with PMOS, Yang et al. conducted a comprehensive review of more than 20 randomized controlled trials examining the effects of vitamin D supplementation on fertility outcomes.
The following six noteworthy findings from the study demonstrate the potential positive impact of vitamin D supplementation on reproductive health in women with PMOS.
Six Findings on the Reproductive Health Benefits of Vitamin D Supplementation in Women with PMOS
1. Higher Pregnancy Rates
The research suggests that vitamin D supplementation may improve pregnancy rates in women with PMOS. Potential mechanisms include reduced inflammation in granulosa cells, improved ovulation, and increased endometrial thickness, all of which may support successful conception and implantation.
2. Improved Ovulation and Increased Egg Maturation
Vitamin D may promote ovulation and the development of mature eggs by supporting granulosa cell function, regulating AMH signaling, and enhancing follicular development. These effects may ultimately contribute to more regular ovulation and improved fertility outcomes.
3. Reduced Early Miscarriage Rates
The study found evidence suggesting that vitamin D supplementation may help reduce the risk of early miscarriage. One proposed explanation is vitamin D’s role in supporting healthy progesterone production, which is critical for maintaining early pregnancy.
4. Lower Testosterone Levels
Vitamin D supplementation was associated with lower testosterone levels in women with PMOS. Researchers suggest this effect may be related to improvements in insulin resistance and increased aromatase activity, which facilitates the conversion of testosterone into estradiol.
5. Improved Reproductive Hormones
Vitamin D supplementation was associated with lower luteinizing hormone (LH) and FSH levels. These effects may result from improved insulin sensitivity, enhanced granulosa cell function, and increased aromatase activity, all of which contribute to healthier ovarian function.
6. Lower Risk of Premature Delivery
The research suggests that vitamin D supplementation may reduce the risk of preterm delivery. This benefit may stem from vitamin D’s anti-inflammatory and immune-regulating effects, which could help lower the risk of infection and pregnancy-related complications.
True Health Matters Summary
These findings further highlight the important relationship between PMOS, vitamin D status, and reproductive health. While additional research is needed to better understand the underlying mechanisms and long-term clinical benefits, the available evidence suggests that maintaining adequate vitamin D levels may support fertility, pregnancy outcomes, and overall reproductive function. These results may also provide a foundation for future therapeutic approaches involving vitamin D supplementation in women with PMOS-related fertility challenges.
References:
[1] Lin MW, Wu MH. The role of vitamin D in polycystic ovary syndrome. Indian J Med Res. 2015 Sep;142(3):238-40. doi: 10.4103/0971-5916.166527. PMID: 26458338; PMCID: PMC4669857.
[2] Mohan A, Haider R, Fakhor H, Hina F, Kumar V, Jawed A, Majumder K, Ayaz A, Lal PM, Tejwaney U, Ram N, Kazeem S. Vitamin D and polycystic ovary syndrome (PCOS): a review. Ann Med Surg (Lond). 2023 Jun 5;85(7):3506-3511. doi: 10.1097/MS9.0000000000000879. PMID: 37427232; PMCID: PMC10328709.
[3] Yang M, Shen X, Lu D, Peng J, Zhou S, Xu L, Zhang J. Effects of vitamin D supplementation on ovulation and pregnancy in women with polycystic ovary syndrome: a systematic review and meta-analysis. Front Endocrinol (Lausanne). 2023 Aug 1;14:1148556. doi: 10.3389/fendo.2023.1148556. PMID: 37593349; PMCID: PMC10430882.
