They found that the poorest patients, particularly those aged over 35 years, were almost three times as likely to develop depression as women from affluent backgrounds.
Similarly, although less dramatic, effects were found for both anxiety and severe mental illness (including bipolar disorder and schizophrenia).
BJGP Editor, Professor Roger Jones said: “Although maternal perinatal mental illnesses commonly present to and are primarily treated in general practice, few population-based estimates of this burden exist, and the most affected socioeconomic groups of pregnant women remain unclear.
“Maternal perinatal mental illness has been highlighted as one of the most important issues in women’s health worldwide and there is considerable burden across the severity spectrum of maternal mental illnesses in UK general practice for women of all ages.
“This research highlights that greater recognition that women in the most socioeconomically-deprived groups are at high risk is required at policy level and should emphasise the need for trials of methods to effectively identify women and interventions to prevent and treat perinatal mental illness in high risk women in the primary care setting.”
This study was printed in the British Journal of General Practice.