Depression is a common disorder in pregnancy and associated with adverse effects for both mother and neonate. Pharmacological treatment and prevention options include mirtazapine. In a series of 56 cases, we investigated neonatal outcome after intrauterine exposure to mirtazapine and exposure through lactation in the first days postpartum.No increase in any neonatal complication was observed. None of the infants exposed to mirtazapine in the first trimester were born with a major malformation. Of the 54 infants exposed to mirtazapine in the third trimester, 14 were diagnosed with poor neonatal adaptation syndrome (PNAS). This incidence (25.9%) is similar to the incidence of PNAS after intrauterine exposure to other antidepressants. The incidence of PNAS after exposure to mirtazapine was significantly diminished in children who were partially or fully breastfed (18.6% versus 54.5%, P = 0.024).