(306) Recreational drug use in Pregnancy: An observational study

Background: Previous studies observed risk of adverse obstetrical and neonatal outcomes following prenatal cocaine and opioid exposure. Yet, they lacked a comparable reference group with identical follow-up to mitigate the effects of confounders associated with substance use in pregnancy.

Objectives: To compare the risk of adverse obstetrical and neonatal outcomes between women who consumed cocaine and/or opioids during pregnancy to women who consumed cannabis only during pregnancy.

Methods: This cohort study included pregnant women followed for addiction issues from the beginning of their pregnancy until delivery in a specialized consultation (Addi-Vie), in CHUV maternity hospital, Switzerland between 2005-2014. The exposed group included women who reported active use of cocaine and/or opioids (illicit or opioid agonist therapy) with or without cannabis in early pregnancy, and the reference group consisted of women who reported active use of cannabis only. Women who reported none of the substances listed above or twin pregnancies were excluded. The primary outcomes were i. Adverse obstetrical composite outcome (presence of at least one of the following outcomes: preterm birth, induction of labor, instrumental birth, and cesarean-section) and ii. Adverse neonatal composite outcome (presence of at least one of these outcomes: small for gestational age, neonatal abstinence syndrome (NAS), Apgar score < 7 at 5 minutes, respiratory distress syndrome, congenital malformation, neonatal infection, and hospitalization for >5 days). Inverse probability treatment weighting (IPTW) was used to control for potential confounders and weighted logistic regression model was conducted to assess adjusted odds ratio (AOR) and 95% confidence interval (CI).

Results: Of 177 pregnant women included, 80 were included in the exposed group and 97 in the reference group. Among the pregnant women included in the exposed group, 81.2% (n=65) reported opioid use and 39.9% (n=32) reported cocaine use in pregnancy. Compared to the reference group, more than half of the exposed infants experienced NAS (57% vs 0%) or were hospitalized for >5 days (65% vs 10.3%). After adjusting for confounders with IPTW, prenatal exposure to cocaine and/or opioids was not associated with the odds of adverse obstetrical composite outcomes (85% vs 76.3%, AOR 0.78, 95%CI: 0.27-2.25). However, the adjusted odds of adverse neonatal composite outcome in the exposed infants were 3.8 times higher compared to the reference group (90% vs 71.1%, AOR 3.81, 95%CI:1.20-12.05).

Conclusions: Cocaine and/or opioid use during pregnancy was associated with an increased risk of adverse neonatal outcome, but not with adverse obstetrical outcomes, when compared to the use of cannabis only in pregnancy.