Introduction: Venlafaxine (Efexor®) is a serotonin and noradrenaline
reuptake inhibitor (SNRI) used for the treatment of
depression and anxiety disorders. The limited data on the use of
venlafaxine in human pregnancy do not indicate an increased risk
of congenital malformations. The main purpose of the study is to
assess the rate of major malformations after first trimester exposure
to venlafaxine.
Methods: This multicenter, prospective cohort study was performed
using data from nine centers who are member of the
European Network of Teratology Information Services (ENTIS).
Data on pregnancy and pregnancy outcome of women who used
venlafaxine in pregnancy were collected during individual risk
counseling. Standardized procedures for data collection and followup
were used by each center.
Results: Follow up data were collected on 744 pregnancies of
womenwhoused venlafaxine during gestation. In 583 (78.4%) cases
the exposure had occurred at least in the first trimester. In total,
there were 600 live births (5 twins), 85 spontaneous abortions, 57
elective terminations of pregnancy, 5 fetal deaths, and 2 ectopic
pregnancies.
The overall rate of major malformations after first trimester
exposure and excluding chromosomal and genetic disorders was
3.2% (16/500) in all pregnancies ending in delivery, pregnancy
terminations or fetal deaths with fetal-pathological examination.
Among live births the malformation rate was 2.7% (13/490). We
observed no increased risk for organ specific malformations.
Conclusions: The present study indicates that venlafaxine is not
a major human teratogen.