Did you know that cannabis use during pregnancy has been linked to adverse birth outcomes? According to researchers at the University of Toronto, infants exposed to cannabis before birth are more likely to be born preterm, have a low birth weight, and require neonatal intensive care. However, the study also found that these infants were not at a greater risk of birth defects or death within the first year. The research highlights the importance of understanding the potential risks associated with cannabis use during pregnancy and provides valuable information for healthcare providers and expectant mothers.
Main Findings
Infants prenatally exposed to cannabis more likely to have adverse birth outcomes
No increased risk of birth defects or infant death
Cannabis use during pregnancy has been found to be associated with adverse birth outcomes, according to a study conducted by researchers at the University of Toronto (U of T). The study, published in the journal Addiction, revealed that infants who were prenatally exposed to cannabis were more likely to be born prematurely, have a low birth weight, and require neonatal intensive care unit (NICU) admission. However, the study also found that there was no increased risk of birth defects or infant death within the first year.
Lead author of the study, Maryam Sorkhou, a PhD student at the Temerty Faculty of Medicine’s Institute of Medical Science, explained that the global increase in cannabis use among women of reproductive age also extends to pregnant women. THC, the main psychoactive compound in cannabis, has the ability to cross the placenta and bind to receptors in the fetal brain, potentially affecting fetal development.
Background
Increase in cannabis use among pregnant women
THC can cross the placenta and affect fetal development
In recent years, there has been an increase in cannabis use among women of reproductive age, including pregnant women. This trend raises concerns about the potential impact of prenatal cannabis exposure on fetal development. THC, the main psychoactive compound in cannabis, has the ability to cross the placenta and bind to receptors in the fetal brain. As a result, it has the potential to affect the normal development of the fetus.
Study Design
Pooling of results from 57 prior studies
Inclusion of over 12 million infants
To investigate the association between prenatal cannabis exposure and adverse birth outcomes, the researchers conducted a systematic review and meta-analysis. They pooled the results from 57 prior studies conducted from 1984 to 2023, which collectively included data from over 12 million infants. These studies examined various health outcomes in infants, including preterm delivery, low birth weight, and NICU admission, among others.
Preterm Delivery
Association between intrauterine cannabis exposure and preterm delivery
Mothers using cannabis more likely to have preterm delivery
Among the studies included in the analysis, twenty of them specifically measured the association between intrauterine cannabis exposure and the risk of preterm delivery. The combined results from these studies showed that mothers who used cannabis during pregnancy were over one and a half times more likely to have a preterm delivery compared to mothers who did not use cannabis.
Low Birth Weight
Association between intrauterine cannabis exposure and low birth weight
Mothers using cannabis more likely to have low-birth-weight baby
In addition to preterm delivery, the researchers also examined the association between intrauterine cannabis exposure and the risk of low birth weight. Eighteen of the studies included in the analysis measured this outcome. The combined results demonstrated that mothers who used cannabis during pregnancy were more than twice as likely to have a low-birth-weight baby compared to mothers who did not use cannabis.
NICU Admission
Association between intrauterine cannabis exposure and NICU admission
Newborns with cannabis exposure more likely to require NICU admission
The analysis also investigated the association between intrauterine cannabis exposure and the likelihood of NICU admission. Ten of the studies included in the analysis measured this outcome. The combined results revealed that newborns with intrauterine cannabis exposure were more than twice as likely to require NICU admission compared to newborns without exposure to cannabis.
Limitations
Potential confounding factors not accounted for in studies
Variability in cannabis use and timing of exposure
While the findings of the study provide valuable insights into the association between prenatal cannabis exposure and adverse birth outcomes, it is important to acknowledge the limitations of the research. One limitation is the potential presence of confounding factors that were not accounted for in the individual studies included in the analysis. Additionally, there is variability in the frequency and timing of cannabis use among the women included in the studies, which can impact the results.
Implications
Importance of educating pregnant women about the risks of cannabis use
Need for further research on long-term effects
The findings of this study highlight the importance of educating pregnant women about the potential risks associated with cannabis use during pregnancy. Healthcare providers play a crucial role in informing and supporting pregnant women in making informed decisions about substance use during pregnancy. Furthermore, additional research is needed to further understand the long-term effects of prenatal cannabis exposure and to develop strategies for prevention and intervention.
Conclusion
Prenatal exposure to cannabis linked to adverse birth outcomes
Awareness and prevention strategies needed
In conclusion, the study conducted by researchers at the University of Toronto reveals that prenatal exposure to cannabis is associated with several adverse birth outcomes, including preterm delivery, low birth weight, and the need for NICU admission. However, there was no increased risk of birth defects or infant death within the first year. These findings emphasize the importance of raising awareness about the potential risks of cannabis use during pregnancy and implementing strategies for prevention and intervention. Further research is necessary to fully understand the long-term effects of prenatal cannabis exposure.
