Do Maternal Pharmacogenetics Impact the Neonatal Abstinence Syndrome Following In Utero Exposure to Antidepressant Medications?

OBJECTIVE: Selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are the most commonly used medications for mood and anxiety disorders in women. Many women need to continue or initiate these medications during pregnancy, but there is concern about potential withdrawal effects in the newborn, referred to as neonatal abstinence syndrome (NAS). The reason why some infants remain asymptomatic while others are affected has not been elucidated. The objective of this study was to examine whether genetic differences in maternal drug metabolism influence the incidence of NAS. METHODS: Women who took Selective serotonin reuptake inhibitors s/SNRIs during pregnancy were recruited from obstetrical clinics. DNA was extracted from saliva samples for genetic analyses of cytochrome P450 (CYP) enzyme polymorphisms. Delivery and NAS data were collected from electronic medical records. RESULTS: Ninety-five women participated. The overall NAS rate was 16.2%. Mild NAS was seen in 13.8% of neonates and severe NAS, in 2%. One-quarter (25%) of the neonates with mild withdrawal symptoms were born to mothers with polymorphisms associated with slower metabolism of their particular antidepressant, but this association was not statistically significant. CONCLUSION: Importantly, the overall rate of NAS in our study was lower than previously reported. Maternal CYP polymorphisms did not affect the rate of NAS in neonates exposed to SSRIs/SNRIs in utero. This study lends added assurance to patients requiring SSRIs or SNRIs during pregnancy.