The Importance of Nutrition in Pregnancy and Lactation: Eat Better, Not More

Title: The Importance of Nutrition in Pregnancy and Lactation: Lifelong Consequences
Journal: American Journal of Obstetrics and Gynecology
Date: May 2022

Most women in the United States do not meet the recommendations for healthy nutrition and weight before and during pregnancy. Women and health care providers often ask what a healthy diet for a pregnant woman should look like. The topic has been the subject of much debate, and has produced inconsistent and sometimes confusing advice for pregnant women who are trying to do the right thing.

In a new paper, three OHSU researchers, along with 12 other national and international researchers, came to consensus about nutrition in pregnancy and during breastfeeding. The paper was birthed, so to speak, out of a 2019 Nutrition in Pregnancy conference, hosted by the OHSU Bob and Charlee Moore Institute of Nutrition & Wellness. The paper, The Importance of Nutrition in Pregnancy and Lactation: Lifelong Consequences, was published May 6, 2022 in the American Journal of Obstetrics and Gynecology.

Incredibly, before 2020, dietary guidelines did not include pregnant or breastfeeding women – or infants under the age of two. That changed in 2020, when both the USDA and National Institutes of Health (NIH) included guidelines and recommendations for infants, toddlers and pregnant women. This paper was authored just prior to those changes being announced, and the findings and recommendations are consistent with the new guidelines. 

Consensus points
The authors arrived at ten points of consensus about nutrition in pregnancy and lactation:

  1. Comprehensive improvements in the nutritional and health status of women before and during pregnancy, will contribute to optimal fetal growth, better outcomes in childbirth, improved perinatal survival, and the potential for better long-term health in both the mother and child.
  2. Low birth weight, small and large for gestational age, fetal growth restriction and other abnormal growth patterns are associated with poor maternal nutritional status.
  3. Dietary patterns of pregnant adolescents are generally less healthy than adult pregnant women. This, during a critical time for their own nutritional status, indicates the need for enhancing diet quality among young pregnant mothers.
  4. There is an association between healthy dietary patterns before and during pregnancy, and a reduced risk for disorders such as gestational diabetes, preterm birth, obesity-related complications, and in some populations, preeclampsia and high blood pressure. Nutrition therapy is used to treat gestational diabetes and is especially important for pregnant women with obesity who have undergone bariatric surgery or who have preexisting diabetes.
  5. Nutritious diets include ample quantities of vegetables, fruits, whole grains, nuts, legumes, fish, oils enriched in monounsaturated fat, and fiber — and are lower in fatty red meat and refined grains. Furthermore, healthy diets avoid simple sugars, processed foods, and trans and saturated fats.
  6. A diet that consistently and substantially restricts any macronutrient should be avoided during pregnancy. Fad diets may be especially harmful during pregnancy because of the resulting nutrient imbalance, nutrient deficiencies or ketosis.
  7. The best time to improve nutrition and BMI is before becoming pregnant. However, having weight gain goals during pregnancy may be more feasible for some women. That would mean limits on foods with empty calories and calorie dense foods may be more achievable. Growing evidence indicates that BMI before pregnancy does affect the degree of influence that gestational weight gain has on pregnancy complications.
  8. Breast milk is uniquely suited to meet the nutritional needs of normal infants born at term for the first 4 to 6 months of life, and its consumption during infancy is associated with lower risks of chronic disease in later life. Breast milk composition is influenced by what the mother eats, and her adipose nutrient stores. Among women with gestational diabetes, there is evidence that exclusive breastfeeding for at least 6 months decreases the risk of Type 2 diabetes for the mother and is protective against the risk of childhood obesity in her offspring.
  9. Regularly consuming multivitamin and mineral supplements that contain optimal amounts of folic acid, among other micronutrients, is recommended for all reproductive-age women to augment a balanced diet, starting at least 2 to 3 months before conception and continuing throughout pregnancy until she stops nursing, or at least 4 to 6 weeks after delivery. Women who become pregnant after bariatric surgery need additional supplements and close monitoring before and during pregnancy.
  10. It is imperative that healthcare providers have the time, knowledge and means to discuss optimal nutrition — and provide educational support to women of reproductive age to improve their health before, during and after pregnancy.

Eat better, not more
The author’s core message, “eat better, not more,” can be achieved by eating a diet based on a variety of nutrient-dense, whole foods that include fish, fruits, vegetables, omega-3 fatty acids and whole grains — in place of poorer quality, processed foods and beverages — to enhance nutritional quality without excessive energy intake.

Nutritional requirements vary by each mothers’ individual characteristics, and in addition to considering dietary quality before pregnancy — factors such as maternal body size, age, gestational age, number of pregnancies, activity level and medical conditions — should be considered. The USDA provides interactive online tools for health professionals to tailor dietary recommendations for women before and during pregnancy — and the MyPlate interactive tool that women can use to plan their diets.

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The OHSU Bob and Charlee Moore Institute for Nutrition & Wellness supports human research that seeks to find the links between maternal stresses, including poor nutrition, and elevated disease risks for babies as they become adolescents and adults.


N.E. Marshall, et al (2019). The importance of nutrition in pregnancy and lactation: lifelong consequences. Am J Obstet Gynecol, 226(5), pp. 607-632