Prematurity and low birth weight among Brazilian adolescents and young adults.

STUDY OBJECTIVE

To compare the incidence of preterm birth and low birth weight infants in young and older primiparous adolescents versus young adults.

DESIGN

Cross-sectional study.

SETTING

Maternity hospital in Vitória, ES, Brazil.

PARTICIPANTS

During a 5-year period, young primiparous women who delivered a singleton liveborn infant over 22 weeks were interviewed while in the postpartum ward.

INTERVENTIONS

A single investigator performed all the individual interviews to collect sociodemographic variables and obtained gestational age and birth weight from the patients' charts before discharge.

MAIN OUTCOME MEASURES

Participants were divided into 3 groups according to age: young adolescents (10-15 years), older adolescents (16-19 y) and young adults (20-24 y). The chi(2) test was used to compare the rate of preterm birth and low birth weight between the groups and analyze differences in sociodemographic characteristics between the 3 groups. P<0.05 was considered significant.

RESULTS

A total of 1124 participants were included: 164 young adolescents, 537 older adolescents and 423 adults. The rate of preterm birth was similar in the 3 groups: 4.3%, 3.5% and 4.5%, for young adolescents, older adolescents and adults, respectively (P=0.48). The rate of low birth weight was significantly higher among young adolescents (9.7%) compared to older adolescents (6.1%) and young adults (3.5%) (P=0.012).

CONCLUSIONS

The rate of preterm birth was similar in adolescents and young adults. Adolescent mothers under 16 years of age have a significantly higher incidence of low birth weight infants.