[Effects of sunlight exposure on vitamin D status in pregnant women in France].

The concentration of 25-(OH)D in the blood were measured in 61 pregnant women between the ages of 16 and 45 who were living in three towns that had different amounts of sun (Lyon, Chambery, Nice). The reason for doing this was to find out the influence of exposure or non-exposure to sun on the vitamin D status of these women. A subclinical lack of vitamin D was found in a number of women where ever they lived, seemingly linked to too little exposure to sun (5% of women exposed to sunshine and 59% of women who were not exposed to sunshine had concentrations of 25-(OH)D (less than 10 ng/ml). In the women who were not exposed to sunshine there was a higher frequency of low concentrations of 25-hydroxy vitamin D (less than 10 ng/ml) in Lyon in winter and in women who came from South Europe, Africa or the Middle East. But 39% of the caucasian women who did not go out into the sun, also had low levels of 25-(OH)D (less than 10 ng/ml). There was a positive correlation between the concentrations of 25-(OH)D in the mothers and in the new born (p less than 0.001) which confirmed the dependence of the infant on his mother to build up reserves of vitamin D. Vitamin D supplements should be given to all women in the last trimester of pregnancy who cannot have enough sunshine, where ever they are living in France, in order to avoid the repercussions of low maternal vitamin D levels for the mother and her new-born infant.