Accurate Canadian prevalence data on drug use in pregnancy is lacking as self reporting is likely to be unreliable and urine screening detects only recent drug exposure. The purposes of this epidemiologic study were to assess:(1) prevalence of drug use in pregnancy, using meconium testing (2) correlation with self-reporting (3) demographics of pregnant drug users.

In part I of the study, meconium was collected anonymously in 10% of all babies delivered at the two maternity hospitals in Vancouver over a 1-year period, and tested for cocaine, opiates, and metabolites by radioimmunoassay. Adequate samples were obtained in 502/545 babies. Meconium screened positive for cocaine and/or opiates in 19 (3.8%) infants: 5/76 (6.6%) from the downtown hospital and 14/426 (3.3%) from the other hospital.

In part II, 563/625 new mothers consented to interviews. Twenty-two (3.9%) reported cocaine and/or opiates use (9 cocaine, 16 opiates), and most of these indicated poly-drug use, alcohol, and/or smoking. Other drug use included: 17 marijuana, 6 tranquilizers, and 6 narcotic analgesic for medical reasons. Of the 470 babies with adequate meconium samples, 8 (1.7%) screened positive for cocaine and/or opiates, a significantly lower positive rate compared with anonymous screening (p=.048).

The prevalence of drug use in pregnancy in Vancouver is low for a port city. Although self-reporting identified a similar number of drug exposed pregnancies as anonymous meconium screening, self-reporters included light drug users, but not all heavy drug users. Self-reporting is not a reliable method of identifying all pregnancies with heavy drug exposure. Supported by grant from Health and Welfare Canada