A review of the epidemiology of nutrition and adolescent pregnancy: maternal growth during pregnancy and its effect on the fetus.

Abstract

Maternal growth during adolescent pregnancy and its effects on pregnancy outcome have been a source of controversy. Maternal growth during pregnancy has been difficult to quantify because of the tendency of young and older women to “shrink” in stature with pregnancy. In the Camden Study, maternal growth during pregnancy was monitored with the Knee Height Measuring Device, which measures growth of the lower leg, a body segment less susceptible to “shrinkage.” Attempts of other investigators to detect maternal growth during adolescent pregnancy are reviewed here. New data from the Camden Study, also presented, suggest that growing adolescents have infants that weigh less compared to nongrowing adolescents and mature controls (aged 19-29 years). Prior work had suggested that the effects of maternal growth on birth weight were confined to adolescent multiparas. However, with expanded enrollment it was found that infants of growing primiparas and multiparas were both affected. The hypothesis of the competition for nutrients between a still-growing gravida and her fetus is discussed.

This review of maternal growth during pregnancy and its effect on fetal development is based on the Camden study of US adolescent growth. The Knee Height Measuring Device (KHMD) is used to measure growth among a cohort of women during pregnancy and delivery in the period July 1987-January 1992. The KHMD is considered more reliable as a measure of growth, is less susceptible to shrinkage during pregnancy, and does not represent an increase in fat mass of the leg during pregnancy. Differences in growth between entry into care and six weeks postpartum indicate a mean increase for teenagers of 0.86 mm compared to a decrease in mature controls of −0.39 mm. Over 80% of adolescents identified as growing with the use of KHMD are truly growing during pregnancy, although only a fraction of the total number who are growing can be detected. Other studies of maternal growth are based on medical records of stature height. Bender observes that pregnancy at very young ages does not pose a threat to maternal nutritional status or fetal growth. Garth finds that young women with the largest weight gains have shrinkage and a downward bias of measured stature. Sukanich et al. also find adolescents with small changes in stature between pregnancies. Developing country adolescent growth patterns are different. Chronic malnutrition leads to later age at menarche, and adolescent growth continues for a longer period of time. Frisancho et al. find that over 40% of pregnant Peruvian adolescents aged under 16 years have not achieved their mother's height. Harrison et al. find that the stature among Nigerian Hausa women aged under 19 years increased by 2.9 cm with increased vitamin and mineral supplementation and prophylactic malaria regimens. Growth without the treatment was only 1.1 cm. Support was provided both for and against maternal growth being related to increased complications and poor birth outcomes. The Camden study finds growing teenagers have significantly smaller infants by 117 grams for primiparas and 206 grams for multiparas compared to mature controls and growing teenagers. Pregnant teenagers found not to be growing had larger infants. About 50% of pregnant adolescents in the Camden study were reported as growing. All studies suggest support for the maternal-fetal competition hypothesis.

• Adolescent Pregnancy
• Americas
• Biology
• Birth Weight
• Body Height
• Body Weight
• Child Development
• Demographic Factors
• Developed Countries
• Developing Countries
• Fertility
• Fetus
• Growth
• Health
• Literature Review
• Low Birth Weight
• Maternal Health
• Maternal Nutrition
• North America
• Northern America
• Nutrition
• Physiology
• Population
• Population Dynamics
• Pregnancy
• Pregnancy Outcomes
• Reproduction
• Reproductive Behavior
• United States