However, it is important to insure that pregnant women don't get too much or too little vitamin A in their diet because both can result in birth deformities. The actual vitamin A requirements for pregnant women are not precisely known. Most of the information has been extrapolated from animal studies, studies of nonpregnant adult women, or reports of women who experience night blindness while on diets of specified vitamin A content. What is known is that most of the increased need for vitamin A occurs in the last three months of pregnancy. This is critical to provide the baby with vitamin A reserves and for sustaining adequate breast-milk concentrations.
Breast milk is the only source of vitamin A for the exclusively breast-fed infant.
The situation is much more critical in non-industrialized countries but, unfortunately, may also be a problem in impoverished areas of the United States and Canada as well. This should entirely meet the demands for nursing and can be accomplished by eating vitamin A-rich foods. Physicians may recommend supplementation if the diet does not provide these amounts. A woman should never take any vitamin supplements without consulting her health care provider.