This study was conducted in order to assess the prevalence of use of selective serotonin reuptake inhibitors (SSRIs) among pregnant women delivering a liveborn infant in the USA. A retrospective study was conducted using the automated databases of 15 health-care systems participating in the Mini-Sentinel program. Diagnosis and procedure codes were used to identify women ages 10 to 54 years delivering a liveborn infant between April 2001 and December 2013. A comparison group of age- and date-matched women without live births was identified. The frequency of use of SSRIs was identified from outpatient dispensing data. Among the 1,895,519 liveborn deliveries, 113,689 women (6.0 %) were exposed to an SSRI during pregnancy during the period 2001-2013; 5.4 % were exposed to an SSRI during 2013. During the corresponding time period, 10.5 % of the age- and date-matched cohort of women without live births was exposed to an SSRI, with 10.1 % exposed to an SSRI during 2013. The most common agents dispensed during pregnancy were sertraline (n = 48,678), fluoxetine (n = 28,983), and citalopram (n = 20,591). Among those women exposed to an SSRI during pregnancy, 53.8 % had a diagnosis of depression and 37.3 % had a diagnosis of an anxiety disorder during pregnancy or within 180 days prior to pregnancy. Our finding that 6 % of women with live births were prescribed SSRIs during pregnancy highlights the importance of understanding the differential effects of these medications and other therapeutic options on the developing fetus and on the pregnant women.