Concurrent decline in teenage fertility rate and binge drinking? An observational study across 45 nations

Alcohol consumption is associated with unintended pregnancies among teenagers. Its role as a broader determinant of teenage fertility rates remains unclear. We investigate whether adolescent binge drinking affects the number of teenage births.

Binge drinking data from 137,898 females aged 15-16 were collected in the HBSC study (2002-2018, 43 countries/regions) and 267,359 in the ESPAD study (1995-2019, 41 countries/regions). Age-specific fertility rates were from the Human Fertility Database and the World Health Organization. We examined changes over time in countries' average levels of binge drinking among female pupils aged 15-16 and population-level fertility rates for the same cohorts when aged 16-19 years.

Controlling for differences between countries and survey waves, we found an association between binge drinking and fertility rate, B = 0.019, 95% confidence interval [0.004, 0.034]. When accounting for the countries' time trends, the association was substantially reduced, B = 0.006, 95% confidence interval [-0.0062, 0.0174]. The relationship was not moderated by abortion rates and controlling for contraceptive use had no impact on the findings.

The association between adolescent binge drinking and fertility rates diminishes when accounting for country-specific time trends. Given the lack of clear mechanisms linking binge drinking to trends in fertility rates rather than shorter-term changes, the association likely reflects broader secular trends. Binge drinking may be involved in teen pregnancy and childbirth in individual cases but it does not explain recent developments in teenage fertility rates.