For High-Risk mothers who used drugs during pregnancy, the majority reported use of marijuana (19.1%) or cocaine (13.1%), with a small number using stimulants (3.0%), prescription opioids (3.0%), or prescription sedatives (1.0%). Eight of these mothers reported using more than one drug. In addition, one Low-Risk mother reported cocaine use during pregnancy. Because of the heterogeneity of maternal drug use during pregnancy, it was not possible to assess the main effect of these exposures. Prenatal drug exposure was used as a covariate in subsequent analyses.
