Concerns have been expressed about possible adverse effects of the use of antidepressant medication during pregnancy, including risk for neonatal pathology and the presence of congenital malformations.

Data from the Swedish Medical Birth Register (MBR) from 1 July 1995 up to 2007 were used to identify women who reported the use of antidepressants in early pregnancy or were prescribed antidepressants during pregnancy by antenatal care: a total of 14 821 women with 15 017 infants. Maternal characteristics, maternal delivery diagnoses, infant neonatal diagnoses and the presence of congenital malformations were compared with all other women who gave birth, using the Mantel–Haenszel technique and with adjustments for certain characteristics.

There was an association between antidepressant treatment and pre-existing diabetes and chronic hypertension but also with many pregnancy complications. Rates of induced delivery and caesarean section were increased. The preterm birth rate was increased but not that of intrauterine growth retardation. Neonatal complications were common, notably after tricyclic antidepressant (TCA) use. An increased risk of persistent pulmonary hypertension of the newborn (PPHN) was verified. The congenital malformation rate was increased after TCAs. An association between use of paroxetine and congenital heart defects was verified and a similar effect on hypospadias was seen.

Women using antidepressants during pregnancy and their newborns have increased pathology. It is not clear how much of this is due to drug use or underlying pathology. Use of TCAs was found to carry a higher risk than other antidepressants and paroxetine seems to be associated with a specific teratogenic property.