With rates of cannabis use during pregnancy more than doubling between 2002 and 2017, a need for more studies, over longer periods of time, which investigate prenatal cannabis use has emerged. Existing data ranges from reporting an increased risk for preterm birth and low birth weight to cannabis reducing the risk of preeclampsia and gestational diabetes during pregnancy. Concerns are historically informed by preliminary alcohol and cocaine studies that falsely suggested no gestational harm, despite the eventual recognition that these substances ultimately carry significant risk. Pregnant women should exercise caution in their cannabis use until more definitive conclusions are found, regarding maternal cannabis use.
The decision of where, if anywhere, cannabis fits in relationship to pregnancy is populated with more questions than answers. There are a handful of good quality, long-term studies, to date, that show a pattern that informs some degree of generalization: by and large, the less frequently consumed, and the later during the pregnancy the consumption, the less potential risk. But, for the sake of any pregnant woman and her baby, this type of decision should always be made in direct consultation with the obstetrician supporting the pregnancy.
Additional Point: A lack of high-quality studies relating to cannabis use and gestational risk has resulted in conflicting evidence surrounding prenatal cannabis use. However, historical context involving prenatal alcohol and cocaine use studies informs the need to exercise caution before definitive conclusions are made
Self-reported Medical and Nonmedical Cannabis Use Among Pregnant Women in the United States
An observational study has revealed that the prevalence and frequency of cannabis use in pregnant women have increased over the past two decades.
No trends were seen although except a slight decrease in fetal growth in women who frequently used during the first two trimesters. The data concerning fetal growth, such as length and weight, were not statistically significant and would require further studies to appropriately indicate a correlation between cannabis use and decreased fetal growth.
The authors acknowledge that cannabis use may suffer from recall bias as women may underestimate the amount of cannabis they consumed or purposely withheld some information due to stigma, although some of the surveyed women were using recommended medical cannabis.
This article highlights the large issue surrounding women consuming cannabis while expecting. Cannabinoids are able to cross the placenta and therefore affect the fetus during development. The American College of Obstetrics and Gynecologists recommend the cessation of any cannabis consumption while pregnant although there has been limited data discussing the actual effects on fetal development. A previously featured article on this blog stated that cannabis use had no effect on birth outcomes but also noted uncertainty in the possible effect on fetal growth. Considering this uncertainty, physicians should push for more research so that women who take medical cannabis can accurately discern whether or not to cease consumption while pregnant.
Statistics show that in the past 15 years, the number of pregnant women using marijuana, especially in their first trimester, has risen greatly. These numbers may be slightly skewed, but they show the importance of more research being done on the effect of cannabis on pregnant women. https://cnn.it/2WWQV1e
In a study of 661, 617 pregnant women, researchers found that cannabis use was significantly associated with an increased risk of preterm birth. But these findings may be limited due to other risk factors like tobacco, alcohol, and opioid use.