Prevalence and related factors of common mental disorders during pregnancy in Japan: a cross-sectional study

Common mental disorders (CMD) during pregnancy can have a clearly harmful influence on both mothers and children. Some studies have reported related factors for mental disorders, such as region-specific background. This study examined the prevalence of CMD and its related factors in mid-pregnancy in Japan. Pregnant women between 12 and 24 weeks gestation and aged ≥20 years were consecutively recruited at a maternity hospital in Japan between May 2014 and September 2014. CMD were diagnosed using the Mini-International Neuropsychiatric Interview (MINI), self-rated depressive symptoms were assessed using the Edinburgh Postnatal Depression Scale, and interpersonal traumatic experience was measured using the Life Events Checklist. Among 297 eligible pregnant women, 177 participated in the study. Two participants (1.1 %) met the criteria for major depressive disorder. The most frequent diagnosis was agoraphobia (n = 7; 3.9 %). Eleven participants (6.2 %) met the criteria for one or more diagnoses, with 2 participants having two mental disorders and 3 having three mental disorders. Six participants developed CMD after gestation. Logistic regression analysis revealed history of psychiatric disorder, past interpersonal traumatic experience, and feeling pressure to have a child were associated with CMD. These findings indicate a lower prevalence of CMD in mid-pregnancy in Japan than reported in most other countries. Besides the related factors reported previously, feeling pressure to have a child might increase risk for CMD among pregnant women in Japan. Asian cultural background might be related to the lower CMD prevalence and risk factors identified in this study.