Title : Examining the relationship between substance use during pregnancy and mode of delivery: Potential variations by substance used
Abstract:
Background: Delivery by Cesarean section (c-section) is a common procedure, and it has well-documented risks for the mother and the neonate. This mode of delivery is associated with maternal mortality and morbidity due to hemorrhage and thromboembolisms, as well as increased labor complications in future pregnancies. The child has increased risks of asphyxiation from anesthesia and neonatal respiratory morbidity. While substance use during pregnancy is relatively common, there is little research available about how this may affect the delivery mode. Proposed mechanisms of substance use during pregnancy leading to increased rate of c-section may include fetal distress, preterm labor, or maternal hypertension.
Objective: The goal of this study was to investigate the relationship between substance use during pregnancy and mode of delivery (c-section versus vaginal).
Methods: Data are from the Maternal-Child EMR Project, which is reviewing electronic medical records of maternal-child dyads at two academic pediatric practices in the U.S. Participants were maternal-child dyads involving children born since July 2016 with pediatric medical records available through age 12 months, with maternal prenatal and delivery records also available. Medical records were manually reviewed for variables including maternal medical history, background factors, and child outcomes. For this project, the first 242 maternal-child dyads were included. In this investigation, the use of different substances (marijuana, tobacco, prescription and non-prescription drugs) during pregnancy were examined in relationship to rates of vaginal delivery versus c-section. Mothers were considered positive for a substance if they self-reported during pregnancy, had a positive drug screen, or if the baby had a positive cord test. The data was analyzed on SPSS using regression models to control for background differences between those who did and did not use substances during pregnancy.
Results: Opioid users had a c-section delivery rate of 47.2% compared to non-drug users’ rate of 32%. After controlling for type of health insurance, maternal race/ethnicity, and prenatal care utilization, it was found that those who used opioids during pregnancy were more than two and a half times more likely to have a c-section than non-opioid users. There were no significant relationships between other substance use and delivery mode.
Conclusions: These results indicate that opioid use during pregnancy is a significant predictor of c-section delivery. Further research with a larger sample size is planned to examine maternal substance use versus sub-types of c-section (elective and emergency), and to explore reasons for this relationship. Additionally, further research is warranted to examine the mechanism of opioids on delivery mode, such as its effect on labor progression, fetal heart rate, and maternal complications.
Significance: Drug use may predict c-section delivery due to its association with obstetric complications, fetal distress, and maternal health issues, which can increase the need of surgical intervention. By conducting cross-substance comparisons, this investigation discerned which substances exhibit an association with increased c-section rates versus vaginal deliveries, thereby providing insights into prenatal care strategies and informed delivery approaches. Since there is a significant relationship between opioid use and c-sections, this can guide providers in adopting knowledgeable delivery strategies.
