Adolescent pregnancy, which occurs in over one million U.S. teenagers each year, remains a major public health and nutrition concern. Nutritional requirements for the adolescent female increase during the time that growth is at its maxium. Although the time of onset, rate, and duration of the growth spurt varies considerably among female adolescents, it generally begins around age ten and is completed by about age fifteen (Morgan, 1984). During this period of rapid growth, the nutritional needs may be as much as doubled when compared to the rest of adolescence (Mahan & Rosebrough, 1984). The increase in lean body mass is associated with growth results in an increased need for protein, iron, zinc, calcium, and folic acid (American Dietetic Association, 1989; Story, 1990). An increased need for iron also occurs due to loss of approximately 15 to 28 milligrams during menstruation (Mahan & Rosebrough, 1984; Morgan, 1984; Story, 1990). Conditions such as illness, physical activity, and pregnancy further increase these nutritional requirements (Morgan, 1984; Story, 1990).
Numerous studies have indicated that black females are at about a two-fold risk for producing low birth weight infants than are white counterparts. A female's general health and nutrition status at conception is a good predictor of pregnancy outcome (Heslin & Natow, 1984). The increase in nutrient requirements as a result of the growth spurt coupled with the possibility of inadequate diets may result in adolescents entering pregnancy with limited nutrient reserves (Story, 1990). As a result of poor pre-pregnant nutritional status, it is possible that pregnant adolescents may deplete their limited nutritional reserves, which can ultimately compromise their health as well as lead to poor pregnancy outcomes (American Dietetic Association, 1989).
Due to the efforts of teenagers to appear slim and to limit weight gain, they are more likely than their older counterparts to be underweight at the beginning of their pregnancy and to gain less than 16 pounds during pregnancy (American Dietetic Association, 1989). Females who are underweight at the beginning of their pregnancy tend to have smaller babies than do heavier women even when gestational weight gains are the same. Also, very young adolescents (less than two years postmenarche) may give birth to smaller babies, for a given weight gain, than do older mothers (Subcommittee on Nutritional Status and Weight Gain During Pregnancy, 1990). Low birth weight increases the risk of perinatal mortality, poor infant development, and impaired growth (Subcommittee of Nutritional Status and Weight Gain During Pregnancy, 1990).
In the United States, approximately 13% of all babies are born to adolescent mothers. By their 18th birthday, 26% of black teenagers and 7% of white teenagers (a total of 533,483 and 194, 984 to 17 and under) will have carried a pregnancy to term (Meredith & Dwyer, 1991). It is fair to say that most of these pregnancies were unplanned and little preparation was given for the physical demands of child bearing. The importance of pre-pregnancy nutrition and its impact on pregnancy outcome as well as the number of pregnant adolescents substantiates the need for research in this area.
The purpose of this study was to examine the preconception nutritional status of black and white, nonpregnant, adolescent females in terms of their pre-pregnancy weight for height as well as their energy, iron, calcium, and protein intakes. Additionally, this study attempted to assess racial differences in dietary intake that may contribute to our better understanding of the high rate of low birth weight in the black female population.
Study Design and Subject Selection
This study was part of a comprehensive, cross-sectional survey of teen health habits. Twenty high schools from three local school districts were stratified and matched according to race and size in order to ensure a representation of black and white students. …