“In a 2020 review of relevant studies published since the mid-1980s, the authors called out many of these studies for weak methodology. In particular, many researchers had failed to compare the outcomes they were measuring against any kind of a standard that would account for age and parental educational level. (That is: What if the kids of those who used cannabis during pregnancy were born to parents with lower levels of education, which could account for some differences?)
The review authors concluded that overall, “prenatal cannabis exposure is associated with few effects on the cognitive functioning of offspring.” What’s more, they noted, even when abnormalities were identified, almost all were still within the range of normal.”
“Despite the imperfect data, Mark suspects the risk of fetal harm with prenatal cannabis use is high enough to support recommending against purely recreational use.
But many aren’t seeking to get high.”
“Studies on marijuana use during pregnancy are inconsistent and inconclusive. But cannabis is not known to be teratogenic—that is, to cause birth defects—in humans. The bulk of scientific evidence suggests that risks posed to developing fetuses are relatively minor and babies exposed to marijuana in utero still fall within normal ranges of outcomes.
A 2020 review looked at longitudinal studies on “the impact of prenatal cannabis exposure on multiple domains of cognitive functioning in individuals aged 0 to 22 years” and found that “evidence does not suggest that prenatal cannabis exposure alone is associated with clinically significant cognitive functioning impairments.” Researchers did note some differences—”those exposed performed differently on a minority of cognitive outcomes (worse on < 3.5 percent and better in < 1 percent)" — although "cognitive performance scores of cannabis-exposed groups overwhelmingly fell within the normal range."
A 2016 review of studies on potential ties between in utero marijuana exposure and adverse birth outcomes—things like low birth weight and preterm delivery to miscarriage and stillbirth—found "maternal marijuana use during pregnancy is not an independent risk factor for adverse neonatal outcomes after adjusting for confounding factors." Instead, any increases in adverse outcomes appeared "attributable to concomitant tobacco use and other confounding factors.""
""The best new evidence on this comes from a 2019 study out of Canada," Oster writes. Matching women who used cannabis with demographically similar women who didn't, researchers did "find evidence of worse birth outcomes among the cannabis users," including "an increased risk of prematurity and NICU transfer. The increases are moderate but statistically significant: preterm birth occurred in 10% of cannabis users and 7% of non-users." An August 2020 study from the same authors found marijuana use correlated with slightly higher incidences of intellectual disability and learning disorders, as well as higher chances of having autism spectrum disorder. "The percent increase is large—about 50%—and significant," Oster points out, though the researchers do note that the overall incidence rate is still small.
Though the researchers tried to demographically match participants between groups, it can still be hard to totally compensate for the ways marijuana users may differ from non-users."
"The biggest problem is that it's hard to isolate specific factors like marijuana consumption. The population of women who not only use marijuana during pregnancy but are also willing to admit to researchers that they do may differ from those who don't."
"A review of evidence published in February 2020 "points to the possibility of lower birth weight, diminished IQ and more behavior problems among children whose mothers used cannabis during pregnancy, but notes it is very difficult to separate the marijuana use from other demographics or other variables,""
" With the limited evidence available, it may make sense for most pregnant women to avoid marijuana to minimize possible risks to their offspring. But the best choice for one woman and her baby won't be the best choice universally. For women who have extreme morning sickness that makes getting adequate nutrients through food and vitamins difficult, and for whom marijuana mitigates nausea, using cannabis might make sense. Likewise, women with certain mental health conditions helped by marijuana may deem it safer than their usual prescription drugs."
“the 2018 maternal mortality rate was 17.4 maternal deaths per 100,000 live births — meaning 658 women died in 2018. The figure includes deaths during pregnancy, at birth, or within 42 days of birth.
The rate once again put the US last among similarly wealthy countries”
“If you compare the CDC figure to other countries in the World Health Organization’s latest maternal mortality ranking, the US would rank 55th, just behind Russia (17 per 100,000) and just ahead of Ukraine”
“black women across the country are 320 percent more likely to die from pregnancy-related complications than white women. In Buncombe County, where Asheville is located, black babies were nearly four times as likely as white babies to die before their first birthday. These woeful statistics cut across economic and educational lines, as pregnant black women with a college degree die at five times the rate of their white counterparts. Experts say the causes are complex and bound up with the stress of living in a society that discriminates against people of color—from a lack of diversity in the medical profession to implicit bias in the way providers treat patients. In 2017, the American College of Obstetricians and Gynecologists said maternal health disparities “ cannot be reversed without addressing racial bias,” adding that “structural and institutional racism contribute to and exacerbate these biases.””