Prenatal vitamins are multivitamins intended for women who are pregnant or hope to become pregnant. Sometimes prenatal
vitamins are
recommended for women who are breast-feeding, too. Most prenatal
vitamins contain more folic acid, iron and calcium than do standard adult multivitamins. Prenatal vitamins have been claimed to promote thicker hair and stronger nails, but researchers haven't yet proved whether prenatal vitamins truly have these effects.