Teenage pregnancy and risk of adverse perinatal outcomes associated with first and second births: population based retrospective cohort study

Objective To determine whether first and second births among teenagers are associated With increased risk of adverse perinatal outcomes after confound ing variables have been taken into account. Design Population based retrospective cohort study using routine discharge data for 1992-8. Setting Scotland. Main outcome measures Stillbirth, preterm. delivery, emergency caesarean se ction, and small for gestational age baby among non-smoking mothers aged 15 -19 and 20-29. Results The 110 233 eligible deliveries Were stratified into first and seco nd births. Among first births, the only significant difference in adverse o utcomes by age group was for emergency caesarean section, which was less li kely among younger mothers (odds ratio 0.5, 95% confidence interval 0.5 to 0.6). Second births in women aged 15-19 Were associated with an increased r isk of moderate (1.6, 1.2 to 2.1) and extreme prematurity (2.5, 1.5 to 4.3) and stillbirth (2.6, 1.3 to 5.3) but a reduced risk of emergency caesarean section (0.7, 0.5 to 1.0). Conclusions First teenage births are not independently associated with ari increased risk of adverse pregnancy outcome and are at decreased risk of de livery by emergency caesarean section. However, second teenage births are a ssociated with an almost threefold risk of preterm delivery and stillbirth.