Postnatal depression in Japanese women who have given birth in England

A total of 98 Japanese mothers who became pregnant in England were monitored from 36 weeks gestation to 3 months postpartum. Psychiatric status was assessed by self-report, using a Japanese translation of the Edinburgh Postnatal Depression Scale (EPDS) and by an interview with Japanese psychiatrists, using Japanese translations of the Schedule for Affective Disorders and Schizophrenia (SADS) and Research Diagnostic Criteria (RDC). Rates of depression were similar to those observed in Japanese women having babies in Japan. Twelve mothers (12%) were categorised as having new onsets of depression (six major and six minor depressive disorder) during the 3 months following delivery. Depression was associated with having had a stressful life event or obstetric difficulty but without grandmothers' support – depressed and non-depressed women were equally likely to have had their mothers visit England to attend the delivery. Women who became depressed had significantly higher EPDS scores at 1 month postpartum than those who remained well. However, depressions were not detected when the EPDS was used as a screening instrument. With an EPDS cut-off of greater than 12, the criterion used in western samples, sensitivity was zero. Lowering the criterion to improve the instrument's sensitivity merely reduced its specificity. These results suggest that Japanese women may be less likely to express depressive symptoms by self-report, at least when instruments designed for western samples are used.