Background: Both antidepressant use and depression in pregnancy have the potential to impact on outcomes for the women, their mother-infant relationship and their infants. Methods: Data were obtained from 485 pregnant women within Mercy Pregnancy and Emotional Wellbeing Study, a pregnancy cohort study. The sampling frame was in three groups: those depressed women taking antidepressants in pregnancy, women with diagnosed depression not taking an antidepressant and control women. Depression was measured using the Structured Clinical Interview for DSM-IV and repeat Edinburgh Postnatal Depression Scale and antidepressant use by repeat self-report, hospital records and blood levels. In addition, data on key maternal, parenting and infant outcomes were collected. Results: This study found, for women taking SNRI antidepressant medication there was an elevated rate of pregnancy hypertension. Infants exposed to antidepressants had lower Apgar scores and higher birth weight and this was not associated with dose or class of antidepressant. In contrast, women with higher depressive symptoms had lower maternal antenatal attachment and higher postpartum parenting stress. Both women with depression and those taking antidepressants were less likely to initiate breastfeeding. On the Ages and Stages Questionnaire, there was a significant difference in communication skills in SSRI antidepressant exposed infants at 12 months. Limitations: Individual antidepressants could not be examined and development was only measured to 12 months Conclusions: Overall, the study identified that antidepressant treatment in pregnancy was significantly associated with only a limited number of poorer maternal and infant outcomes and was not associated with poorer parenting outcomes.