The Role of Vitamin D in Pregnancy

You no doubt have heard a lot of talk about the health effects of Vitamin D, but how does this vitamin relate to fertility and pregnancy?  In a way that is a bit of a trick question because Vitamin D is really not a vitamin but a hormone.

From a structural stand point it looks very similar to the sex hormones such as estrogen, testosterone, and progesterone.  Looking from a functional side, Vitamin D is used to send messages to cells and triggers a change in those cells, just like other hormones.

So what specifically does Vitamin D do?  One of its major functions is to "prime" or prepare cells for other hormones to be able to work properly.  This is where Vitamin D's role in conception comes in.  For ovulation and conception to occur, not only do your major hormones (estrogen and progesterone) need to be in proper balance, but so to the role playing hormones, such as the thyroid hormones, cortisol, DHEA, testosterone, and yes Vitamin D. 

The level of circulating Vitamin D can play a role in resolving fertility issues associated with poly cystic ovarian syndrome (PCOS) and lack of ovulation.  Of course there is the other side of the fertility issue.  Low levels of Vitamin D leads to decreased sperm motility and production.  So guys should be tested for Vitamin D levels also if there are fertility problems.

What about when you are pregnant?  One study reports evidence that Vitamin D plays a role in implantation, normal placental development and prevention of eclampsia.

You can imagine, if Vitamin D is so important to hormone activity, just how important it would be to the developing baby.  Studies have demonstrated a healthy levels of maternal Vitamin D in pregnancy are associated with a decreased likelihood of asthma, respiratory infections, Type I diabetes and even multiple sclerosis. 

Knowing and monitoring your Vitamin D levels pre-conception and throughout pregnancy makes sense and is easy to do with a simple at-home finger stick test that we order through our office.