Megan Galbally, Stuart J. Watson, Doug Teti, Andrew J. Lewis

Both perinatal depression and infant sleep problems are common concerns in many communities, with these problems often coinciding. Findings in this area conflict and much of the research relies on poor measures of sleep and/or depression. Adding to this complexity is the rise in antidepressant treatment for perinatal maternal depression and no previous study has examined the relationship between such exposure and infant sleep. This study draws on four waves of data (early pregnancy and third trimester, and six and 12 months postpartum) from 264 women in the Mercy Pregnancy and Emotional Wellbeing Study, a prospective pregnancy cohort study of women recruited in early pregnancy in Melbourne, Australia. Cross-lagged regression models were used to examine reciprocity of longitudinal effects between depressive symptoms and infant sleep. Maternal antepartum depression and antidepressant use were not significant predictors of infant sleep problems. Likewise, infant sleep problems were not significant predictors of postpartum maternal depression. However, maternal cognitions about infant sleep, characterised by maternal expectations to immediately attend to their crying child, did demonstrate positive reciprocal effects with infant nocturnal waking between six and 12 months postpartum. Infant sleep outcomes were reported by the mother and the sample were predominantly Anglophone, restricting generalizability of the models to other cultures. Maternal depression and antidepressant use were not found to be significant factors in infant sleep problems and, likewise, infant sleep problems were not associated with maternal depression. However, postpartum maternal cognitions around six months postpartum regarding limit-setting at night may predict increases in later nocturnal infant signaling.