Prenatal Nutrition Health Article

Definition

Maternal nutrition during pregnancy affects both the health of the mother and the growing fetus. Requirements for calories and specific nutrients are increased for the baby's growth and proper development. These needs can be met by increasing healthful food consumption and specific nutrient supplementation.

Purpose

Proper prenatal nutrition helps ensure a healthy start for a new baby and promotes the mother's well-being during and after pregnancy. Nurses and other allied health professionals can play a role in educating pregnant women about sufficient weight gain, the importance of a healthy diet, and the following recommendations for supplementation.

Precautions

Maternal weight gain during pregnancy is an important predictor of a baby's birth weight. The height and weight of the mother before pregnancy should be taken into account when assessing maternal nutrient needs. Both underweight and excessively overweight women need special attention. Underweight women are more likely to give birth to premature or low birth-weight infants, while overweight women have an increased risk of developing pregnancy-related complications. Other high-risk groups for low birth-weight babies include women younger than 15 and those older than 35. Women whose pregnancies are fewer than 12 months apart are also at higher risk.

Description

Maternal weight gain is a measure often used to assess how well a pregnancy is progressing. Normal weight gain is considered to be 25 to 35 pounds, although individual needs should also be taken into account. Women who are underweight to start with may benefit from gaining more (28-40 pounds), while overweight women may try to gain less (15-25 pounds). Even for overweight women, however, weight gain is important to allow for proper growth of the fetus.

Nutrient needs during pregnancy depend on physical activity and metabolism of the mother. For most women, energy needs increase to about 300 extra calories per day during the second and third trimesters. Protein needs increase to allow for new tissue growth and maintenance; deficiency can result in lower a birth weight. An extra 10 to 12 grams of protein per day is recommended during the last half of pregnancy.

Vitamin and mineral requirements are also increased during pregnancy. To meet those needs, most women in the United States are advised to take a multivitamin supplement with minerals while they are pregnant. Eating a well-balanced diet with plenty of fruits, vegetables, and whole grains will also help provide the needed vitamins. Iron and calcium are two minerals of special concern. The fetus acquires most of these minerals during the last trimester of the pregnancy. Doctors recommend daily supplementation of 30 mg of iron in the form of ferrous sulfate to avoid iron deficiency anemia, which can cause excessive tiredness in the mother. Calcium intake should be 1,200 to 1,500 mg per day, which can be obtained through diet or supplementation. Adequate calcium is important so that the mother does not lose bone mass during pregnancy. There is also some evidence that calcium supplementation reduces the risk of pregnancyinduced hypertension, also known as preeclampsia, for women who are at high risk for this condition.

Folate (folic acid) is an extremely important vitamin, not only during pregnancy, but before pregnancy as well. Folate is crucial to the development of new cells, and deficiency during pregnancy has been associated with the development of congenital malformations known as neural tube defects (NTDs). The most serious NTDs include spina bifida and anencephaly. Spina bifida is characterized by gaps in the spine, typically resulting in serious lifelong disability. An infant with anencephaly lacks brain formation and dies shortly after birth. Because NTDs arise early in pregnancy, before most women know they are pregnant, the U.S. Public Health Service recommends that all women of childbearing age consume 0.4 mg (400 micrograms) of folic acid daily. Adequate amounts of folate can be obtained from the diet, but in practice most women do not consume enough. To help address this problem, in 1996 the U.S. Food and Drug Administration (FDA) approved folate fortification of flour, breads, cereal, and rice.