Sex difference in parental risk of suicide attempt during and after pregnancy in Sweden

Whether the risks of maternal and paternal suicide attempt during and after pregnancy differ remains unclear. Here, in this nationwide register-based study in Sweden (2,196,276 pregnancies), we defined the year before conception, pregnancy and the year after birth and estimated week-specific incidence rate ratios (IRRs). We identified 7,469 (1.39 per 1,000 person-years) suicide attempts among mothers and 8,338 (1.62 per 1,000 person-years) among fathers. Compared with the corresponding week in the preconception period, mothers had a lower risk of suicide attempt during and after pregnancy (with the lowest IRR of 0.14 (0.11-0.17) at first week postpartum); fathers' risk of suicide attempt remained largely stable before childbirth, but a lower risk was observed during the first 10 postpartum weeks (IRRs ranging from 0.69 (0.58-0.81) to 0.91 (0.84-0.99)), followed by a higher risk in the later postpartum period (IRRs ranging from 1.10 (1.01-1.21) to 1.72 (1.33-2.24)). Compared with fathers, mothers had a lower risk of suicide attempt during and after pregnancy (for example, IRR of 0.22 (0.18-0.28) at first week postpartum). Compared with the general population, the sex difference of suicide attempt is reversed during and after pregnancy, suggesting pregnancy or childbirth may have a more pronounced association with suicide attempt among mothers than fathers.