Study provides key insights into pregnant women's use of marijuana

Reviewed by Kate Anderton, B.Sc. (Editor)Feb 4 2020

As the use of marijuana is legalized in an increasing number of U.S. states, the number of people who use the drug daily is on the rise. This upward trend also holds up in women who are pregnant or breastfeeding, despite evidence that using marijuana could harm their babies.

Published in the Journal of Addiction Medicine, findings from a study conducted by a team of researchers at Washington State University Health Sciences Spokane delve deeper into pregnant women's use of marijuana, providing key insights that will help inform patient education efforts. Their study was conducted in Washington State and is the first study of its kind conducted in a state where marijuana is legal.

"We don't have all the research, but there's enough there to warrant saying that you should not use marijuana while pregnant," said lead author Celestina Barbosa-Leiker, citing prior research that suggests marijuana use during pregnancy it is associated with increased risk of low birth weight, still birth, and cognitive and behavioral issues. "Yet, there's a group of women who are using marijuana that have these other chronic conditions, and we need to help them manage those."

An associate professor in the WSU College of Nursing and the vice chancellor for research at WSU Health Sciences Spokane, Barbosa-Leiker said that, based on their findings, pregnant women's health care providers should more fully consider patient history and engage in a shared decision-making process with them about their marijuana use. She suggested health care providers adopt a harm reduction approach focused on limiting marijuana use, rather than asking women to go cold turkey. In addition, she said it's important to train all health care staff to interact with patients in a way that minimizes stigma.

Many of the moms we spoke to reported feeling incredibly stigmatized as soon as they reported that they were using marijuana. The worst thing that could happen is that one of these moms feels so uncomfortable that she doesn't come back for prenatal care, which is detrimental to the health of the baby."

Celestina Barbosa-Leiker, lead author

Five themes emerge from study

As part of their study, the WSU research team conducted personal interviews with 14 pregnant women and 5 women who had given birth within the past three months, all of whom reported using marijuana daily while pregnant. They asked the women questions related to their perceptions of the risk and benefits of using marijuana during pregnancy. From the participants' responses, they identified five common themes:

• Participants reported using marijuana as a way to manage their health issues, from physical issues such as nausea, pain, and difficulty sleeping to psychological issues such as stress, anxiety, and trauma. Many made this decision not just for themselves, but also for their baby. One woman reported that using marijuana was the only way she could keep food down, providing critical nourishment to her baby. Others said it helped them reduce stress and anxiety and function better as a parent.
• Many carefully weighed their decision to continue marijuana use during pregnancy and reevaluated their use through each phase of the pregnancy and after giving birth. One common reason why they used marijuana was to avoid using other medications they felt were more harmful to their baby, such as opioids, anti-nausea drugs, and anti-psychotic medications.
• Pregnant women are getting mixed messages from their health care providers. Mostly their providers told them to stop using marijuana, but some were asked to limit their use. A few women reported not ever being asked about marijuana use or their provider not saying anything when they disclosed it, which surprised the researchers given national guidelines that direct health care providers to counsel pregnant women about the risks of using marijuana.
• All participants said they wanted more information on the safety and effects of using marijuana while pregnant. When women felt that medical providers were not giving them enough information, they sought out advice from other sources, such as budtenders.
• Legal considerations appear to be driving whether or not pregnant women disclose their marijuana use to health care providers, as well as their pattern of use during pregnancy. Fear of being reported to child protective services made some women decide to stop using toward the end of their pregnancy, when test results might have exposed their marijuana use.

Barbosa-Leiker said the study completely changed her perspective.

"Going into the study, I thought that showing these women the research about how it impacts their baby would make them change their behavior," she said. "Once I heard these women's stories of going through incredibly traumatic experiences and making very brave choices to keep themselves and their babies as healthy as possible, it made me realize that we need to do a better job of knowing patients' perspectives before we try to get them to adopt healthier behaviors," she said.

In addition to providing key insights that can help health care providers better focus their patient education efforts, Barbosa-Leiker said the study also highlights the need for more research to determine the long-term effects of marijuana use during pregnancy and breastfeeding.