Mental Disorders and Having a First Child Among Young Adults: A Nationwide Register-Based Cohort Study

To examine associations between mental disorders and time to first childbirth in Finland, and whether partnership status mediates these associations.

Nationwide register-based cohort study.

Primary and secondary healthcare data from Finland.

All individuals born in 1980-1995 who were childless and living in Finland at age 16 (n = 1 210 662).

Cox proportional hazards models to examine associations between mental disorders and time to first childbirth. Participants were followed until first childbirth, death, emigration, or the end of 2019.

Time to first live childbirth.

Both men and women diagnosed with mental disorders had a lower likelihood of becoming parents compared to those without diagnoses. People diagnosed with schizophrenia and intellectual disabilities were the least likely to become parents. Adjusting for partnership status attenuated the associations for all mental disorders. Before age 25, substance use, childhood onset, anxiety, or any mental disorders were associated with a higher likelihood of first childbirth, but after age 30, mental disorders were linked to a lower likelihood of parenthood.

Almost all mental disorders were associated with a lower likelihood of having a first child among young people born in 1980-1995. These findings imply that well-functioning mental health services are important from a fertility perspective.