Assessing the net effect of young maternal age on birthweight.
Pregnancy during adolescence presents an increased risk for low birthweight, which is attributed not only to physiologic immaturity but also to socioeconomic and behavioral risk factors associated with adolescence. The independent effect of maternal age on birthweight is difficult to ascertain because age is closely entangled with these risks. We first examined the effect of being an adolescent mother on these risk pathways and then estimated the net effect of maternal age on birthweight (weight in grams or low birthweight (<2500 g)) after controlling for these risks. We used data on 214 adolescent and 415 adult primiparae and their infants from the Cebu Longitudinal Health and Nutrition Survey, a community-based survey in Metro Cebu, Philippines. Consistent with findings from other studies, adolescents in this sample were more socioeconomically disadvantaged, had poorer nutritional status during pregnancy, and received less prenatal care than adults. Bivariate analyses showed that infants of adolescents had a lower mean birthweight and were more at risk of low birthweight compared to those born to older mothers. When socioeconomic, biological, and behavioral risk factors were controlled for, young maternal age ceased to have an effect on birthweight in grams but remained a significant predictor of low birthweight. The common pathways through which maternal age influenced both birthweight variables were through its effects on maternal height and weight-for-height during pregnancy. In the model predicting birthweight in grams the maternal age effect was further manifested through prenatal care utilization.
Borja
Judith B
JB
Office of Population Studies, University of San Carlos, Cebu City, Philippines 6000. jborja@unc.edu
Adair
Linda S
LS
D000293:Adolescent; D000328:Adult; D001724:Birth Weight; D001824:Body Constitution; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008423:Maternal Age; D009752:Nutritional Status; D010679:Philippines; D011247:Pregnancy; D011295:Prenatal Care / Q000706:statistics & numerical data; D011446:Prospective Studies; D011897:Random Allocation; D012307:Risk Factors; D012959:Socioeconomic Factors