Objective: To identify the association between pre-gestational nutritional status, maternal weight gain, and prenatal care with low birth weight (LBW) and prematurity outcomes in infants of adolescent mothers.
Methods: Cross-sectional study with 542 pairs of adolescent mothers and their children attending a public maternity hospital in Rio de Janeiro. Data were collected from medical records. To determine the association between independent variables and the outcomes studied, odds ratio (OR) and a 95% confidence interval (CI) were estimated
Results: With respect to pre-pregnancy nutritional status of adolescents, 87% had normal weight, 1% were underweight, 10% were overweight, and 2% obese. Inadequate total gestational weight gain (72%) exceeded adequacy (28%). Birth weight was favored with greater gestational weight gain, and reduced with late onset of prenatal care. The comparison between the low birth weight and normal birth weight groups revealed significant differences between variable means: interval between the past pregnancy and current pregnancy (p = 0.022), pre-gestational weight (p = 0.018); pre-gestational body mass index (p < 0.001), and total gestational weight gain (p = 0.047). The odds of LBW (OR 2.70, 95% CI 1.45 to 5.06) and prematurity (OR 5.82, 95% CI 3.10 to 10.92) fell when the adolescent received six or more prenatal visits.
Conclusion: Birth weight was associated with inter-gestational interval, pre-pregnancy weight and body mass index before pregnancy. The minimum frequency of six prenatal care visits was a protective factor against LBW and prematurity.