Objective
To re-evaluate the impact of England's Teenage Pregnancy Strategy (1999 to 2010) on pregnancy and birth rates. Hailed as a unique, nation-wide, comprehensive, evidence-based intervention, the strategy has been promoted as a reproducible model for other countries with high teenage pregnancy rates.
Design
Controlled interrupted time series and synthetic control analyses using routinely collected data on births and abortions in 16 countries.
Setting
The Strategy was published in July 1999 and implemented from 2000-2010, with increased investment in areas with higher rates of under-18 pregnancies from 2006 onwards.
Participants
Women aged under 20 living in England during the intervention period were considered to be the target population. Women in Scotland and Wales were the control population in our interrupted time series analyses. Women from European and English-speaking high-income countries were the control population in our synthetic control analyses.
Main outcome measures
The pregnancy rate among women aged under-18 was our primary outcome, as this was the target of the Strategy. We used under-18 births and under-20 pregnancies as secondary outcomes.
Results
In the controlled interrupted time series analyses, trends in rates of teenage pregnancy in England were similar to Scotland (0.08 fewer pregnancies per 1,000 women per year in England; -0.74 to 0.59) and Wales (0.14 more pregnancies per 1,000 women per year in England; -0.48 to 0.76). In synthetic control analyses, under-18 birth rates were very similar in England and the synthetic control. Under-20 pregnancy rates were marginally higher in England than in the synthetic control. Placebo testing and other sensitivity analyses supported the finding of no observable effect.
Conclusion
Although teenage pregnancies and births in England fell following implementation of the Teenage Pregnancy Strategy, comparisons with other countries suggest the strategy had little, if any, effect. The strategy should not be used as a model for future public health interventions in England or in other countries.
The protocol for the analysis was published online at https://osf.io/tdbr8/
Did England's Teenage Pregnancy Strategy reduce pregnancy rates in England? A Natural Experiment study