ObjectiveTo assess obstetric outcomes in teenage pregnancies in a country with a low teenage delivery rate and comprehensive high-quality prenatal care.DesignRetrospective population-based register study.SettingFinland.ParticipantsAll nulliparous teenagers (13–15 years (n=84), 16–17 years (n=1234), 18–19 years (n=5987)) and controls (25-year-old to 29-year-old women (n=51 142)) with singleton deliveries in 2006–2011.Main outcome measuresRisk of adverse obstetric outcomes adjusted for demographic factors and clinically relevant pregnancy complications, with main focus on maternal pregnancy complications.ResultsTeenage mothers were more likely than controls to live in rural areas (16% (n=1168) vs 11.8% (n=6035)), smoke (36.4% (n=2661) vs 7% (n=3580)) and misuse alcohol or drugs (1.1% (n=82) vs 0.2% (n=96); p<0.001 for all). Teenagers made a good mean number of antenatal clinic visits (16.4 vs 16.5), but were more likely to have attended fewer than half of the recommended visits (3% (n=210) vs 1.4% (n=716)). Teenagers faced increased risks of several obstetric complications, for example, anaemia (adjusted OR 1.8, 95% CI 1.6 to 2.1), proteinuria (1.8, 1.2 to 2.6), urinary tract infection (UTI; 2.9, 1.8 to 4.8), pyelonephritis (6.3, 3.8 to 10.4) and eclampsia (3.2, 1.4 to 7.3), the risks increasing with descending age for most outcomes. Elevated risks of pre-eclampsia (3.7, 1.5 to 9.0) and preterm delivery (2.5, 1.2 to 5.3) were also found among 13-year-olds to 15-year-olds. However, teenage mothers were more likely to have vaginal delivery (1.9, 1.7 to 2.0) without complications. Inadequate prenatal care among teenagers was a risk factor of eclampsia (12.6, 2.6 to 62.6), UTI (5.8, 1.7 to 19.7) and adverse neonatal outcomes.ConclusionsPregnant teenagers tended to be socioeconomically disadvantaged versus controls and faced higher risks of various pregnancy complications. Special attention should be paid to enrolling teenagers into adequate prenatal care in early pregnancy.

The retrospective nature of the study remains a limitation and the quality of the data is reliant on the accuracy of reporting. We were not able to link repeat TOPs of the same woman in our data set. However, the share of repeat abortions was moderate. WIDER IMPLICATIONS OF THE FINDINGS The rate of teenage TOP seems to rapidly reflect changes in national sexual and reproductive health services and policy. The rising rate of repeat TOP is alarming and may represent a sign of marginalization among these girls. All efforts to maintain a low rate of teenage pregnancy are welcomed.

A low educational level is associated with the increased risk of premature death among women with a history of teenage pregnancy, except for suicide. Extra efforts should be made to encourage pregnant teenagers to continue education, and to provide psychosocial support to teenagers who undergo induced abortion.