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Nutrition in pregnancy

Christine D Garner, PhD, RD
Section Editor
Charles J Lockwood, MD, MHCM
Deputy Editor
Vanessa A Barss, MD, FACOG


Pregnancy is a period of intense fetal growth and development, as well as maternal physiological change. Adequate intake of macronutrients and micronutrients during pregnancy promotes these processes, while undernutrition and overnutrition can be associated with adverse pregnancy outcomes [1-5]. Therefore, it is important to evaluate, monitor, and, when appropriate, make changes to improve maternal nutrition both before and during pregnancy.

The effects of inadequate or excessive intake of certain nutrients can be observed in the short-term, but possibly also in the long-term. The developmental model for the origins of disease (ie, Barker Hypothesis) hypothesizes that the fetal environment causes epigenetic modifications that impact gene expression and thereby influence development of disease in children and adults [6]. Seminal studies of the health status of adult offspring of a cohort of women who were pregnant during the Dutch famine in World War II support this hypothesis [7,8].

Many questions remain unanswered due to the many challenges of performing high-quality research in pregnancy [9]. These challenges include the often unknown critical windows when nutrition may impact development, the many physiologic changes that occur over the course of normal pregnancy, the large individual differences in maternal adaptation to pregnancy, ethical and practical issues of experimenting with human pregnancy, challenges with determining effects of specific nutrients in the context of a whole diet, and the lack of a good animal model that can be directly extrapolated to humans.

This topic will discuss basic nutritional concerns related to normal pregnancy, primarily for women living in developed countries. Nutritional therapy of diabetes in pregnant women, in-depth information on specific topics related to maternal nutrition, and basic nutritional issues in healthy nonpregnant adults are reviewed elsewhere. For example:

(See "Healthy diet in adults".)


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