Researchers in Sweden looked at more than one million fathers whose children were born between 2003 and 2021. They checked when each dad got a new mental‑health diagnosis, starting a year before the pregnancy and ending when the child turned one year old.
What the Numbers Show
During the pregnancy and the first few months after birth, fewer dads were diagnosed with mental‑health problems compared with the year before the pregnancy.
But about a year after the baby arrived, the picture changed. Diagnoses for depression and stress‑related conditions went up by more than 30 % compared with the pre‑pregnancy period. Anxiety and substance‑use diagnoses returned to their original levels.
Why It Matters
The study used only clinical diagnoses, so dads who never visited a doctor are not counted. Still, the findings point to a time when fathers can feel especially vulnerable.
“Knowing when dads are most at risk helps doctors and families give the right help,” says researcher Jing Zhou. “We often talk about post‑natal depression for mothers, but fathers need support too.”