Vitamin D and Fertility
Vitamin D is vital for proper body functioning. Besides playing a key role in calcium and phosphorus metabolism in the body, it has a major impact on the fertility in both males and females. Recent animal studies have implicated vitamin D as a major regulator of fertility. This is why maintaining the levels of vitamin D in the body through diet, sunlight and supplements is imperative.
How Does Vitamin D Affect Fertility in Women?
The receptors for Vitamin D are found in a lot of places in the human body. Receptors are the channels by which vitamin D exerts its effects on the body. In females, vitamin D receptors are found in the uterus, placenta, and the ovaries.
- When calcitriol (the activated form of vitamin D) binds to the receptors, it helps control, the genes involved in the production of estrogen (the female hormone). It regulates the production of two key fertility hormones in females-estrogen and progesterone.
- Calcitriol controls the genes involved in implantation of the fertilized egg in the uterus.
- During pregnancy, the uterus and placenta make calcitriol to strengthen the immunity and to ward off the infections.
- Women with high vitamin D levels are more likely to get pregnant after receiving in vitro fertilization (IVF) therapy (assisted conception method) as compared to the women who are vitamin D deficient.
- Vitamin D is known to play a causative role in polycystic ovarian syndrome (PCOS).
- Vitamin D supplementation improves menstrual irregularities.
- It also regulates ovulation and thereby, the chances of getting pregnant.
The Impact of Vitamin D on Fertility in Men
Receptors for vitamin D exist in the testes and sperms in males.
- Vitamin D affects the sperm structure and sperm count. Low vitamin D level leads to low sperm count and motility.
- Vitamin D regulates the structure of testes which is why vitamin D depletion in the body results in histological abnormalities of the testis.
- Vitamin D improves the semen quality in males.
- It is known to improve the levels of the male androgen hormone testosterone.
Sunlight is a natural source of vitamin D. Dietary sources of vitamin D include dairy products, egg yolk, cheese, fish etc. Fortified supplements are also available to combat the deficiency of vitamin D. Maintaining the concentration of vitamin D within the body from various sources ensures optimal reproductive health and fertility in both men and women.
References
http://www.ncbi.nlm.nih.gov/pubmed/22275473
http://www.eje-online.org/content/166/5/765.short
http://www.nhs.uk/news/2012/01January/Pages/vitamin-d-fertility.aspx
http://uscfertility.org/fertility-treatments/vitamin-d-fertility/