Kaiser Permanente of Northern CA screened at 8 weeks prenatal visit (waived consent) from 2009 through 2016, prevalence of prenatal marijuana use based on self-report or toxicology (urine drug screens) increased from 4% to 7%, and was higher based on toxicology than self-report each year.
CA study showed 22% of pregnant females younger than 18 years and 19% of pregnant females aged 18 to 24 years screened positive for marijuana use in 2016.
WOW: 79% of 785 pregnant women surveyed between 2007 and 2012 reported perceiving “little to no harm in prenatal use.” Studies show tobacco use decreasing while marijuana use increasing.
In 2001, THC (tetrahydrocannabinol) screening 7.2% positive in meconium stool samples in US babies.
In 2006, 14% positive in UK (Scottish) babies in 2006. Prevalence may be as high as 15-30% in poor, disadvantaged US moms.
Marijuana potency risen, legal recreational use in 10 states plus DC, approved for medicinal use in 32 states. Pregnant women with severe nausea and vomiting had four times greater odds of marijuana use that women without.
Use of marijuana being touted on social media as effective and safe. Amazingly, 77% of Canadian pregnant women used for nausea, poor appetite, insomnia, pain, and mood disorder, although ACOG clearly states no indication for use in pregnancy.
In 2016, 9% of pregnant women in Vermont use mjrijuana; Surveys show 45% continue to smoke MJ thru pregnancy. With counselling about THC effects 78% abstain from use!
THC (tetrahydrocannabinol) readily crosses placenta.
THC Is highly lipophilic, so it gets into fetal brain and fetal fat cells. Fetal blood levels of THC are 1/3 to 1/10 maternal levels. Smoking marijuana causes higher carbon monoxide (CO) levels than cigarettes!
Marijuana use in pregnancy associated with lower birth weight, less head circumference, slightly higher rate premature birth.
Marijuana use in pregnancy produces significant pervasive effects:
By age 1, less motor development, by age 4 lower verbal reasoning and memory tasks, at 6 years less language comprehension and reading, at age 9-12 years deficits in executive function and impulse control, by 13-16 years deficits in problem solving and sustained attention, at 18-22 years, fMRI showed altered neural activity in working memory tasks.
Higher rates of substance abuse at ages 14-21, independent of other environmental factors.
