Maternal use of selective serotonin reuptake inhibitors during pregnancy and neonatal bone density

Selective serotonin reuptake inhibitors (SSRI) are commonly used to treat depression in pregnant women. Several adverse effects of prenatal SSRI exposure on the offspring have been described, including decreased growth. SSRI use by adults decreases bone mineral density, but this effect had not been examined in infants.

To examine growth parameters and bone mineral density of infants born to mothers using SSRIs during pregnancy.

Anthropometric variables and bone density were compared between 40 newborns exposed to SSRIs in utero, and 40 gestational-age matched control infants. Tibial bone speed of sound, a marker of bone density and strength, was measured using quantitative ultrasound. The difference in bone speed of sound between the two groups was compared using linear models, adjusting for relevant confounders.

Infants in the SSRI-exposed group were shorter, with a marginal statistical significance (49.3±2.1 vs. 50.1±1.3cm, p=0.07), while mean birth weight did not differ substantially between study groups. Head circumference was significantly smaller in the SSRI group (33.8±1.2 vs 34.4±1.1cm, p=0.005), remaining so even after adjustment for several confounders. No considerable difference was found in the bone speed of sound between SSRI-exposed infants and controls (3011±116 vs. 3029±129m/s).

We found no evidence that prenatal SSRI exposure hindered neonatal bone quality, yet a marginally shorter length and a smaller head circumference raise the possibility of an effect on bone growth. We conclude that the effect of SSRIs on fetal bone density seems minimal or absent.