Vitamin D and Human Reproduction—Evolving perspectives

We are all well versed with the role of Vitamin D in maintaining calcium and phosphorus homeostasis and promoting bone mineralization. Its deficiency is linked to many chronic diseases of the cardiovascular and metabolic systems.

Evidence from animal and human studies suggests that vitamin D plays a very important role in human fertility and neonatal development. This steroid hormone has Vitamin D receptors (VDR) at multiple sites in the body including ovary, particularly the granulosa cells, endometrium and placenta.

It plays a very important role in ovarian steroidogenesis. [1] It deficiency contribute to development of insulin resistance and impaired glucose metabolism in patients with Polycystic Ovary Syndrome (PCOS). Therapeutic efficacy of supplementation with Vitamin D to improve insulin resistance, bring about ovulation and regularize menstruation in PCOs patients have been documented.[2] [3]

Observations also shows that lower 25(OH)D levels put women at higher risk of developing uterine fibroids, both in black and white ethnicities. In these women, the growth and size of the fibroid is also directly related to decreased levels of Vitamin D. Animal studies and human in vitro studies have shown the beneficial effect Vitamin D supplementation in inhibition of development and/or growth of uterine fibroids.[4] [5]

A recent study by Harris HR et al demonstrated that women within the highest quintile of Vitamin D blood values have one fourth the risk of developing endometriosis as compared to those in lowest quintile.[6]

It also plays a role in Body Mass Index (BMI) as per a recent meta-analysis, every 10% increase in BMI leads to 4% decrees in Vitamin D concentration.[7]

It’s role in male reproductive physiology is well documented by the fact that it’s level directly correlate with sperm motility and morphology.

As per Hill’s criteria a causal relationship between Vitamin D deficiency and negative outcome in IVF is explained but further research into knowing the magnitude of association is needed.[8]

A systemic review and meta-analysis by Lerchbaum E and Obermayer-Pietsch B published in Eur J Endocrinol May 1, 2012 concludes that Vitamin D plays an important role in Human reproduction and advocates the need of further research in therapeutic benefits of Vitamin D supplementation in such patients.  

Another review by Vanni et al published in the Reproductive Biology and Endocrinology, 2014 emphasizes the importance of supplementation of Vitamin D in IVF settings because consisting evidence documenting the increase incidence of gestational diabetes, IUGR, pre-eclampsia and preterm births in patients deficient in Vitamin D.[9]

The authors opine that although drastic improvements in reproductive failure may not be achieved solely by supplementing Vitamin D, but its addition to any fertility regimen is cheap, effective and without any side effects. It is easily correctable by simple oral supplementation.

Dosage up to 4000 IU is safe, without any side effects and effectively improve maternal vitamin D status. [10]

Results of double blind randomized trial entitled “Vitamin D during IVF” is still awaited.[11]

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[1]Anagnostis P, Karras S, Goulis DG: Vitamin D in human reproduction: a narrative review. Int J Clin Pract. 2013, 67 (3): 225-235

[2] Selimoglu H, Duran C, Kiyici S, Ersoy C, Guclu M, Ozkaya G, Tuncel E, Erturk E, Imamoglu S: The effect of vitamin D replacement therapy on insulin resistance and androgen levels in women with polycystic ovary syndrome. J Endocrinol Invest. 2010, 33 (4): 234-238.

[3] Wehr E, Pieber TR, Obermayer-Pietsch B: Effect of vitamin D3 treatment on glucose metabolism and menstrual frequency in polycystic ovary syndrome women: a pilot study. J Endocrinol Invest. 2011, 34 (10): 757-63.

[4] Bläuer M, Rovio PH, Ylikomi T, Heinonen PK: Vitamin D inhibits myometrial and leiomyoma cell proliferation in vitro. Fertil Steril. 2009, 91 (5): 1919-1925.

[5] Halder SK, Osteen KG, Al-Hendy A: Vitamin D3 inhibits expression and activities of matrix metalloproteinase-2 and −9 in human uterine fibroid cells. Hum Reprod. 2013, 28 (9): 2407-2416.

[6]  Harris HR, Chavarro JE, Malspeis S, Willett WC, Missmer SA: Dairy-food, calcium, magnesium, and vitamin D intake and endometriosis: a prospective cohort study. Am J Epidemiol. 2013, 177 (5): 420-430.

[7] Vimaleswaran KS, Berry DJ, Lu C, Tikkanen E, Pilz S, Kiraki LT, Cooper JD, Dastani Z, Li R, Houston DK, Wood AR, Michaëlsson K, Vandenput L, Zgaga L, Yerges-Armstrong LM, McCarthy MI, Dupuis J, Kaakinen M, Kleber ME, Jameson K, Arden N, Raitakari O, Viikari J, Lohman KK, Ferrucci L, Melhus H, Ingelsson E, Byberg L, Lind L, Lorentzon M, et al: Causal relationship between obesity and vitamin D status: bi-directional Mendelian randomization analysis of multiple cohorts. PLoS Med. 2013, 10 (2): e1001383-

[8] Hill AB: The environment and disease: association or causation?. Proc R Soc Med. 1965, 58: 295-300.

[9] Aghajafari F, Nagulesapillai T, Ronksley PE, Tough SC, O’Beirne M, Rabi DM: Association between maternal serum 25-hydroxyvitamin D level and pregnancy and neonatal outcomes: systematic review and meta-analysis of observational studies. BMJ. 2013, 26 (346): f1169-

[10] Wagner CL, McNeil R, Johnson DD, Husley TC, Ebeling M, Robinson C, Hamilton SA, Hollis BW: Health characteristics and outcomes of two randomized vitamin D supplementation trials during pregnancy: a combined analysis. J Steroid Biochem Mol Biol. 2013, 136: 313-320.

[11] https://clinicaltrials.gov/ct2/show/NCT01019785