A feasibility study to assess the recruitment and retention of pregnant patients who regularly use cannabis

To assess first-trimester recruitment and retention of pregnant patients who regularly used cannabis, but not other substances, measured by willingness to participate in a research study, completion of self-administered electronic questionnaires, and willingness to provide urine samples during each trimester of pregnancy. We designed and launched a prospective feasibility study titled, Cannabis Legalization in Michigan (CALM) – Maternal & Infant Health (MIH), in two Michigan clinics after the recreational use of cannabis became legal for adults 21 years and older.

Over half (52%) of patients asked to participate in CALM-MIH were consented to the study. Two-thirds (66%) of screened patients initiated prenatal care during their first trimester of pregnancy and 50% used cannabis, of which the majority did not concurrently use other substances. Of those recruited into the prospective study, all participants completed the first-trimester questionnaire and provided urine samples. Study retention was 80% and all participants who completed follow-up assessments were willing to provide urine samples.