Cannabis is the most commonly used illicit substance during pregnancy. Given the risks of prenatal cannabis use, effective interventions are needed to support pregnant people in cutting back or quitting. Regular physical activity can play a supportive role in reducing substance use in general, and is also recommended for a healthy pregnancy. Taken together, cannabis reduction interventions that incorporate physical activity may offer multiple benefits for pregnant people. This week, STASH reviews a study by Cynthia L. Battle and colleagues that investigated the usefulness of a walking intervention to reduce cannabis use during pregnancy.
What were the research questions?
(1) What are the effects of a walking intervention for pregnant individuals on: cannabis use, physical activity, and symptoms of depression and anxiety? (2) What is the acceptability and feasibility of this intervention?
What did the researchers do?
The researchers recruited 16 pregnant adults (12–25 weeks gestation) from OB-GYN clinics in Rhode Island and online. Participants had used cannabis weekly before pregnancy, wanted to reduce or stop use, and reported symptoms of depression and/or anxiety, among other inclusion criteria. They took part in a 10-week walking intervention designed to gradually increase physical activity, which included six clinician-led sessions focused on building step goals over time, along with Fitbit tracking of daily steps. The researchers used descriptive statistics and paired t-tests to examine cannabis use, changes in physical activity, and depression and anxiety symptoms post-intervention. They assessed feasibility based on adherence to the intervention, and acceptability based on interviews about participants’ experiences.
What did they find?
Most participants (88%) completed the intervention, attending an average of 5.8 out of 6 sessions. Overall satisfaction was very high. At the start of the intervention, 62.5% of participants were using cannabis. Following the intervention, cannabis use decreased to 16.6% at 36 weeks gestation, but increased to 50% at one month postpartum. Depression and anxiety symptoms decreased from the start to the end of the intervention and remained lower postpartum. Physical activity also increased, with moderate increases in average daily step counts over the course of the program (see Figure).
Figure. Feasibility, acceptability, and early outcomes of a 10-week walking intervention to reduce prenatal cannabis use. Click image to enlarge.
Why do these findings matter?
These findings suggest that a walking intervention to reduce cannabis use during pregnancy is useful and well-received. Participants reduced both cannabis use and symptoms of depression and anxiety, which is important since some pregnant people use cannabis to manage stress or mental health symptoms. For providers, it’s important to understand why pregnant patients may use cannabis and help them find alternative ways to cope. The findings also point to the potential value of combining physical activity with evidence-based approaches. Finally, the increase in cannabis use postpartum highlights the need for support beyond pregnancy, including return-to-cannabis-use prevention and continued guidance from providers to promote longer-term abstinence or moderated use.
Every study has limitations. What are the limitations of this study?
This was not a randomized controlled trial because there was no control group, and the study was not designed to definitively test effectiveness. We cannot conclude that changes in cannabis use were caused by the intervention, particularly given participants’ pre-existing motivation to change and the strict eligibility criteria, which may have introduced bias. Further research is needed to better understand the intervention’s effectiveness and how it could be implemented in practice.
For more information:
Pregnant and parenting people can access the Pregnancy and Substance Use Toolkit from the National Harm Reduction Coalition. The SAMHSA National Helpline is a free addiction treatment and information service available 24/7. For additional general resources and tools, visit the BASIS Addiction Resources page.
— Kira Landauer, MPH
Want CE credit for reading BASIS articles? Click here to visit our Courses Website and access our free online courses.