cannabis exposure in utero; cannabis next to pregnant belly

In Utero Cannabis Exposure Could Cause Offspring Diabetes

New research coming out of the Schulich School of Medicine & Dentistry indicates that cannabis exposure in utero can have harmful life-long health repercussions in the offspring. While it may seem like common sense to some to abstain from cannabis use while pregnant, some women believe consuming the plant while pregnant would be beneficial to reduce anxiety, nausea, and increase their appetite. However, the research concludes that this can cause high rates of morbidity, causing life-long diseases like diabetes and heart disease.

The study

When pregnant lab rats were exposed to the psychoactive chemical in cannabis (tetrahydrocannabinol or THC), their offspring suffered greatly. The rats were exposed to small amounts of cannabis every day of their pregnancy. The goal of the study was to determine if cannabis exposure in utero affected birth weight and other metabolic functions.


Study observations

The researchers observed the following among the pregnant rats:

  • The rats, like humans, eventually built up a tolerance to THC over time.
  • The pregnant rats were unaffected by the THC exposure.
  • The pregnant rats did not experience increased appetites (a notorious side effect of cannabis use).
  • Litter size and gestational length of the offspring were unaffected.

The following effects were observed in the offspring:

  • Exposed offspring were 8-10 percent smaller, a wide margin for a rat.
  • Offspring had a lower organ-to-body weight ratio (30% heart, 40% liver, and 20% reduced brain weight).
  • Their hearts were smaller but had a much higher heart rate.

Offspring diabetes

The most alarming discovery was that the offspring had a 60 percent reduction in beta cells, the insulin-producing cells found in the pancreas. This nearly guarantees a diagnosis of diabetes, although these rats would have type 2 diabetes, as type 1 diabetes would be a complete loss of beta cell function.

Even more alarming, offspring organs continue to develop for up to three weeks after birth while in a “plasticity phase.” During this time, organs can somewhat repair themselves. However, the organs of the exposed offspring were unable to do so after prolonged exposure to cannabis. Researchers concluded that if the test subjects didn’t have enough beta cells by the three-week point, they would never grow them.


Previous studies

Previous studies have looked at the impact of cannabis exposure on the brain, which causes issues like anxiety and social disorders. This is the first study of its kind to study metabolic effects of cannabis exposure in offspring.

If you are pregnant and considering using cannabis, talk to your doctor about the health problems it could cause your future child.