How do pregnancy outcomes differ in teenage mothers? A Western Australian study

Abstract

Objectives: To determine whether teenage pregnancy and Indigenous status are associated with increased risk of adverse pregnancy outcomes.

Design, setting and participants: A cross-sectional descriptive analysis of nulliparous women with singleton pregnancies who delivered at the sole tertiary obstetric hospital in Western Australia between June 2004 and September 2006, using data obtained from computerised midwifery records.

Main outcome measures: Maternal risk factors, pregnancy characteristics, and obstetric and perinatal outcomes for teenage and adult pregnancies.

Results: Of the 4896 births reviewed, 560 (11%) were to teenage mothers. Teenagers were more likely to be Indigenous and to experience maternal risk factors such as anaemia and smoking. Indigenous women were more likely than non-Indigenous women to be smokers, with young Indigenous teenagers (aged 12-16 years) being most likely to smoke (odds ratio [OR], 6.29; 95% CI, 3.99-9.92). Perinatal outcomes for teenage and adult births were similar, while adjustment for smoking and Indigenous status changed the observed association for the Indigenous population of preterm delivery < 37 weeks' gestation (OR, 1.31; 95% CI, 1.01-1.71), admission to special care nursery (OR, 1.41; 95% CI, 1.10-1.81) and low birthweight (OR, 1.43; 95% CI, 1.10-1.87). However, older teenagers (aged 17-18 years) were the group at highest risk of stillbirth (OR, 1.99; 95% CI, 1.03-3.76).

Conclusions: These results improve our understanding of the obstetric and medical issues associated with teenage pregnancy and birth in WA and how we might tailor our approach to care. Indigenous teenagers need special attention, and there is significant scope for public health interventions around anaemia and smoking in this population.