Perinatal drug exposures pose a significant health hazard for women an
d imperil normal fetal and neonatal development. Little is known about
patterns of drug exposure among pregnant immigrant and native-born La
tinas in the United States. We present multivariate risk factor analys
es for alcohol and illicit drug use from the California Perinatal Subs
tance Exposure Study using a statistical probability sample (N = 11,00
2) of Latinas who were tested anonymously using urine toxicology scree
ning techniques. Alcohol use during pregnancy was pervasive among both
immigrant and United States-born Latinas (7%) with little variation o
n risk factors. Illicit drug use was found primarily in a high risk gr
oup of United States-born Latinas between 25 and 34 years of age who r
eceived no prenatal care (prevalence 50%, odds ratio of 185). Increase
d general awareness of perinatal alcohol risk by medical providers and
public health practitioners serving this population is needed. The po
tential isolation of United States-born Latinas who are at risk for us
ing illicit drugs during pregnancy requires effective communication an
d outreach.