Marijuana, also known as pot or weed, is derived from the dried portion of the Cannabis sativa plant. Many studies have been discovering its medical uses, but the drug is still illegal for recreational use in many states. Recently, it was found that pregnant women use weed to alleviate nausea and other pregnancy symptoms, which raises the questions: Is marijuana safe for the fetus? What are its potential effects?
A Rise of Pregnant Women Using Cannabis
On October 16, the Food and Drug Administration (FDA) publicized a statement warning pregnant mothers to avoid products with the main compounds of cannabis: THC (which causes the ‘high’) and CBD.
“FDA strongly advises against the use of cannabidiol (CBD), tetrahydrocannabinol (THC), and marijuana in any form during pregnancy or while breastfeeding,” the agency wrote. They also advised to “Always talk with your doctor, nurse, or pharmacist before taking any medicines, vitamins, or herbs while pregnant or breastfeeding.” 
Despite this warning, many women choose to use cannabis to alleviate pregnancy symptoms like nausea, pain, and postpartum depression. After all, cannabis has been shown to help similar symptoms in other instances, like nausea and vomiting after chemotherapy. 
A 2018 national drug survey found marijuana use during pregnancy has increased from 2.9% in 2002 to 5% in 2016.  A 2014 analysis studied 4,700 Hawaiin women and discovered that they were more likely to use marijuana while pregnant if they suffered from nausea.
“I used marijuana during pregnancy to ease my nausea as well as to help me sleep,” Laiken, 26, who withdrew her last name to protect her identity, told Insider. “It seemed I was constantly up at night and part of that was [because of] nausea.”
Laiken had first tried anti-nausea medications but they didn’t help, so she began using marijuana, which she had used before pregnancy. She consumed it two or three times a day when she felt nausea rising, either through drinking cannabis oil or smoking it in a pipe. 
“We use [cannabis] in chemotherapy patients when they have nausea, so patients think that it’s a good solution for morning sickness,” Dr. Jennifer Leighdon Wu, an obstetrician-gynecologist at Lenox Hill Hospital in New York.
“But when you think about morning sickness, it happens typically in the first trimester, when the brain and other organs are developing, so that’s the time when you really don’t want to be using [cannabis].” 
The Effects of Cannabis on Pregnancy
The U.S. Surgeon General issued a warning for pregnant women using cannabis, stating THC can enter the fetus through the mother’s bloodstream and disrupts the baby’s brain development, and causes lower birth weight.  A study in Colorado in June 2018 found that women who used weed during their pregnancies had a 50% chance of their babies having lower birth weights. 
The American College of Obstetricians and Gynecologists states, “Women who are pregnant or contemplating pregnancy should be encouraged to discontinue marijuana use. Women reporting marijuana use should be counseled about concerns regarding potential adverse health consequences of continued use during pregnancy.” 
Three large-scale longitudinal studies tracked prenatal cannabis use on child development. The Ottawa Prenatal Prospective Study surveyed 700 pregnant women and followed 200 of those children into adulthood. The U.S.-based Maternal Health Practices and Child Development Study studied 580 children of marijuana users from pregnancy through adolescence. The Generation R study tracks almost 8,000 children in the Netherlands. The results were shockingly conclusive.
Children of cannabis users tended to be more impulsive and hyperactive, exhibited behavioral issues, lower IQ scores, and trouble with memory compared to kids of non-users. These issues tended to follow the children into teenagerhood where they were more likely to have depression, attention problems, and display delinquent behavior and likely to use marijuana and tobacco as adults. 
“Unfortunately, the marijuana industry continues to peddle a lie that their superstrength THC is somehow good for pregnant women,” said Kevin Sabet, president of Smart Approaches to Marijuana.
“This phenomenon is part of a wider story: The pot industry is trying to convince America they have a miracle drug — one that can fill state coffers, end the opioid crisis, cure cancer, rid streets of violent cartels, and, now, help pregnant women,” he added. “It is Big Tobacco all over again.” 
However, there are many professionals in the medical field who disagree with these findings.
“What we know today is pretty sparse,” Kjersti Aagard, a maternal-fetal medicine specialist and professor at Baylor College of Medicine and Texas Children’s Hospital. “We don’t have the long-term studies to really examine that carefully from a public health perspective.” 
A study involving over 600,000 pregnant women and over 9,000 cannabis users found a higher risk of poor birth outcomes among the latter group, primarily premature birth and small birth size. However, Emily Oster, an economist at Brown University, commented that the study is not perfect. For example, the researchers did not observe other measures of health such as body weight in their subjects, nor the form of marijuana (smoking, vaping, or edibles) or in what term of pregnancy was the drug consumed. 
Also, cannabis hasn’t been tested on pregnant women because researchers worry about harming the mother and the fetus, so data is limited.
Another limitation is the illegalization of drugs, which makes expecting mothers reluctant to report cannabis use to researchers or their own doctors.
“There are three main types of punitive policies related to drug use during pregnancy at the state level,” Sue Thomas, Ph.D., a senior research scientist at the Pacific Institute for Research and Evaluation (PIRE) in California.
“Women may be reported to Child Protective Services, women may be involuntarily committed in either jail or treatment settings, and women may face allegations of child abuse or neglect and possible termination of parental rights.” She added that women of color and women with low incomes are particularly susceptible to these policies. 
Until more in-depth research is complete, many doctors and health experts recommend expecting women to avoid marijuana use.
For those suffering from nausea and vomiting from their pregnancy, the American College of Obstetricians and Gynecologists recommends taking a combination of vitamin B6 and the sleep aid doxylamine to alleviate the symptoms. 
- FDA. What You Should Know About Using Cannabis, Including CBD, When Pregnant or Breastfeeding https://www.fda.gov/consumers/consumer-updates/what-you-should-know-about-using-cannabis-including-cbd-when-pregnant-or-breastfeeding October 16, 2019
- Linda A Parker, Erin M Rock, and Cheryl L Limebeer. BJP. Regulation of nausea and vomiting by cannabinoids https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3165951/#b84
- Arpana Agrawal, Ph.D.; Cynthia E. Rogers, MD; Christina N. Lessov-Schlaggar, Ph.D. Alcohol, Cigarette, and Cannabis Use Between 2002 and 2016 in Pregnant Women From a Nationally Representative Sample https://jamanetwork.com/journals/jamapediatrics/article-abstract/2712359 January 2019
- Julia Naftulin. InsiderWomen are using marijuana to cope with pregnancy symptoms like nausea even though the FDA warns against it https://www.insider.com/fda-dont-use-marijuana-during-pregnancy-many-moms-do-2019-10 October 29, 2019
- Office of Surgeon General VADM Jerome Adams. U.S. Surgeon General’s Advisory: Marijuana Use and the Developing Brain Background. https://www.hhs.gov/surgeongeneral/reports-and-publications/addiction-and-substance-misuse/advisory-on-marijuana-use-and-developing-brain/index.html#footnote17_muwsac1 August 29, 2019
- Crume TL, Juhl AL, Brooks-Russell A, Hall KE, Wymore E, Borgelt LM. Cannabis Use During the Perinatal Period in a State With Legalized Recreational and Medical Marijuana: The Association Between Maternal Characteristics, Breastfeeding Patterns, and Neonatal Outcomes. https://www.ncbi.nlm.nih.gov/pubmed/29605394 June 2018
- ACOG Committee Opinion. Marijuana Use During Pregnancy and Lactation https://www.acog.org/Clinical-Guidance-and-Publications/Committee-Opinions/Committee-on-Obstetric-Practice/Marijuana-Use-During-Pregnancy-and-Lactation?IsMobileSet=false October 2017 (Reaffirmed 2019)
- Kristen Fischer. Healthline. Experts Worried as More Pregnant Women Use Cannabis https://www.healthline.com/health-news/why-are-more-pregnant-women-using-cannabis#Data-dilemmas? November 19, 2018
- Harvard. How Marijuana Exposure Affects Developing Babies’ Brains http://sitn.hms.harvard.edu/flash/2019/marijuana-exposure-affects-developing-babies-brains/ January 16, 2019
- Emily Oster. The Atlantic. New Evidence on Pot During Pregnancy https://www.theatlantic.com/ideas/archive/2019/07/smoke-pot-during-pregnancy/593101/ July 8, 2019
- Heather Cruickshank. Healthline. Here’s Why Experts Are Worried About Marijuana Use During Pregnancy https://www.healthline.com/health-news/more-women-are-using-marijuana-during-pregnancy-heres-what-can-happen#Some-pregnant-women-may-not-report-cannabis-use July 22, 2019
- the American College of Obstetricians and Gynecologists. Morning Sickness: Nausea and Vomiting of Pregnancy. https://www.acog.org/Patients/FAQs/Morning-Sickness-Nausea-and-Vomiting-of-Pregnancy?IsMobileSet=false December 2018