Cannabis-Exposed Babies Face Poorer Metabolic Health

Babies’ metabolic health appeared to suffer after being exposed to cannabis in the womb, researchers reported.

In a sample of 103 mother-child pairs from Colorado, about 15% of pregnant women tested positive for detectable levels of any type of cannabinoid at around 27 weeks gestation, Brianna F. Moore, PhD, of the Colorado School of Public Health in Aurora, and colleagues wrote in the Journal of Clinical Endocrinology and Metabolism.

Compared with babies who weren’t exposed to cannabinoids in utero, those who were exposed saw a slew of poorer metabolic outcomes by early childhood (mean age 4.7 years):

• Higher fat mass: 1.0 kg (95% CI 0.3-1.7)
• Higher fat-free mass: 1.2 kg (95% CI 0.4-2.0)
• Higher adiposity: 2.6% (95% CI 0.1-5.2)
• Higher fasting glucose: 5.6 mg/dL (95% CI 0.8-10.3)

“We would encourage women to refrain from using any cannabis while pregnant or breastfeeding to minimize adverse health effects in the offspring,” Moore said in a statement. “More studies are needed to understand how exposure to different cannabinoids during pregnancy may impact the offspring.”

However, no differences were seen for fasting insulin in the adjusted model or for insulin resistance (HOMA-IR), BMI, or BMI z-scores.

“This finding may suggest that fetal exposure to cannabis contributes to higher fasting glucose levels via a direct effect on the pancreatic beta cells,” they suggested. “However, we cannot draw conclusions about beta-cell response to glucose because we did not perform oral glucose tolerance tests.”

Moore’s group took a subsample of participants from the Healthy Start cohort study. Models were adjusted for several factors including maternal age, household income, maternal race/ethnicity, fetal exposure to tobacco and childhood exposure to secondhand smoke, prepregnancy BMI, gestational weight gain, offspring sex, gestational age at birth, birthweight, duration of exclusive breastfeeding, and childhood age at follow-up.

The researchers tested for 12 types of cannabinoids and cannabinoid-metabolites in urine samples, the majority of which belonged to the tetrahydrocannabinol (THC) family. The most common cannabinoid was THC-9-carboxylic acid glucuronide, which was detected in 12% of mothers with a maximum concentration of 778.9 ng/mL.

Childhood metabolic measures were based upon blood draws and adiposity measures taken with whole body air displacement plethysmography, BodPod.

In additional to poorer metabolic outcomes in early childhood, offspring that were exposed to cannabinoids in utero were also more likely to be female and have a significantly lower birth weight. These offspring were also more likely to also be exposed to tobacco in utero, as well as in early childhood.

Between the exposed and unexposed groups, there were no differences in maternal age, prepregnancy BMI, gestational weight gain, maternal race/ethnicity, household income, maternal education, gestational age at birth, or the duration of exclusive breastfeeding.

Although a strength of the study was that cannabis exposure was measured via urinalysis and wasn’t self-reported, exposure was only measured at one point during pregnancy. This limited the ability to differentiate between secondhand exposure to cannabis versus active maternal use.