Major depressive disorder is common among women in child-bearing age, and medical treatment is subject to substantial discussions and controversies. For Selective Serotonin reuptake inhibitors, SSRIs, a vast amount of data are available. For the newer antidepressant group of serotonin and noradrenaline reuptake inhibitors, SNRIs, significantly less data are available. Following the PRISMA guideline for systematic reviews, we performed a systematic search on the risk of major congenital malformations after first trimester in utero exposure to venlafaxine or duloxetine. We identified eight cohort studies reporting on the outcome upon in utero exposure to venlafaxine or duloxetine during the first trimester. The cumulated data for venlafaxine were 3186 exposed infants and 107 major malformations, resulting in a relative risk estimate and 95% confidence interval of 1.12 (0.92-1.35). The corresponding data for duloxetine were 668 infants and 16 major malformations, resulting in a relative risk estimate and 95% confidence interval of 0.80 (0.46-1.29). First-trimester in utero exposure to venlafaxine is not associated with an increased risk of major congenital malformations. The amount of data for duloxetine are significantly smaller but does not suggest a clinically important increased risk.Depression is common among women of child-bearing age. Approximately 20% of all women of child-bearing age will experience a depression during their life time, and 1% to 8% will use an antidepressant drug during pregnancy [1]. Untreated depression during pregnancy carries risk of severe consequences to the pregnant mother and her unborn child such as: epidural analgesia, caesarean section, intensive ward admission, preterm delivery, low birthweight, and disturbances in the child's neurocognitive and socio-emotional development [2]. Untreated depression during pregnancy increases the risk of post-partum depression 6-fold [3,4].The controversy of possible untoward foetal effects after in utero exposure to selective serotonin receptor inhibitors (SSRIs) has been ongoing for more than a decade. Data on more than 50,000 first-trimester SSRI-exposed newborn have accumulated, and it is accepted that first-trimester exposure to any antidepressant does not result in an overall increased risk of congenital malformations. The risk of cardiovascular malformations is still somewhat unclear, but if true, absolute risks are minor and may pertain to specific SSRIs, especially paroxetine and fluoxetine [5][6][7][8][9][10]. Comparatively, pregnancy data on the newer combined serotonin/noradrenaline receptor inhibitors (SNRI), venlafaxine and duloxetine, are scarce. A recent large Scandinavian study did not suggest an increased risk associated with venlafaxine [10], and a recent commentary concluded that the amount of information for duloxetine was too little [11].Current guidelines are vague and offer little decision support. The NICE guideline does not distinguish between the various types of antidepressants and offers no direct suggestio...