Males born in summer months reported higher depression symptom scores than males born during other seasons, according to a study from Kwantlen Polytechnic University. Anxiety symptoms showed no association with season of birth for either sex.
Anxiety and depression remain among the most common mental disorders worldwide, with both conditions contributing to long-term disability, physical comorbidities, and substantial economic losses. A range of factors shape mental health across the lifespan, including housing, income, education, and age. Research into early-life exposures remains limited, particularly exposures shaped by environmental seasonality.
During gestation, exposure to temperature shifts, maternal diet, seasonal infections, and variation in daylight may influence neurodevelopment. Birth season has previously been associated with risk for psychiatric conditions including schizophrenia, bipolar disorder, and schizoaffective disorder. Studies examining birth season and depression have produced mixed results, often without stratifying by sex.