Vitamin D is critical in the second trimester.
Babies born to moms who had low levels of vitamin D are more likely to have signs of tooth decay at 16 months than babies whose mothers had adequate levels of the vitamin during pregnancy. This calcium-absorbing vitamin is critical in the second trimester, prime time for babies' primary teeth to develop and calcify. Because the body produces vitamin D through sun exposure, women with darker skin are at particular risk of not getting enough. Boost your vitamin D by snacking on dairy products fortified with the vitamin, safely enjoying the sunshine (especially in winter) and remembering to take your prenatal vitamins.