Children born in the month of May are indicated to have low levels of Vitamin D due to lower exposure to sun than those born in November. Vitamin D deficiency is considered to affect the development of immune system thereby increasing the risk of MS in those who are born in the month of May.
Scientists at Queen Mary, University of London, and the University of Oxford analyzed the cord blood samples of 50 babies born in May and 50 babies born in November. The results indicated that vitamin D levels in blood samples of babies born in May were 20% lower than in those born in November. May babies also contained an increased amount of harmful autoreactive T-cells, which are responsible for autoimmune disease likely MS.
However, the authors conclude that long term researches are needed to establish the effect of pre-natal vitamin D supplements on immune system and risk of autoimmune diseases.