There is a strong link between low vitamin D concentrations in women and lower live birth rates after assisted reproduction therapy (ART) compared to women who have the right amount of vitamin D in their bodies. That’s the conclusion of a review and analysis of data from 11 published studies that included 2,700 women who were undergoing ART and whose vitamin D status had been checked through blood tests.
The study was published in the journal Human Reproduction. The researchers found that live births were a third more likely to occur in women who had the right amount of vitamin D when compared to women who did not. A similar result was seen when the researchers looked at the results of pregnancy tests and clinical pregnancies (where a fetal heart beat could be detected). When compared with women who had deficient or insufficient concentrations of vitamin D, women who had sufficient vitamin D were 34% more likely to have a positive pregnancy test and 46% more likely to achieve a clinical pregnancy. No associations were found between miscarriage and vitamin D concentrations.
The main source of vitamin D for people is sunlight. In the winter months it can be hard to get enough vitamin D and, in addition, some people are more at risk of vitamin D deficiency, for example those who don’t get outdoors much, people with dark skin from African, African-Caribbean and south Asian backgrounds, and people who wear clothes that cover most of their skin when they are outdoors. Foods such as oily fish, red meat, liver and egg yolks also provide vitamin D, as well as vitamin D supplements.
Talk to your doctor before taking any supplements, including vitamin D.