Cannabis use has a slightly elevated risk of infertility due to ovulation abnormalities. Some women continue Cannabis use during pregnancy to reduce pregnancy symptoms such as morning sickness and prenatal anxiety & depression despite contradicting evidence that Cannabis use may have negative effects on their developing fetus and child development.
Cannabis & Pregnancy Studies
Using Cannabis while pregnant has not been associated with an increased risk of infant. Morality. However, using Cannabis frequently throughout pregnancy may be associated with reduced birth weight. Two large studies have been performed on heavy Cannabis use during pregnancy by the Ottawa Prenatal Prospective Study (OPPS) and the Maternal Health Practices and Child Development study (MHPCD). The Ottawa Prenatal Prospective Study and the Maternal Health Practices and Child Development study both examined the effects of Cannabis use during pregnancy.
On children of mainly Caucasian, middle-class Canadian mothers while the Maternal Health Practices and Child Development study studied the effects of prenatal Cannabis exposure and children of a group of mothers. This study group contained half African-American mothers and the other half was Caucasian.
These studies showed that there wasn’t a higher rate of miscarriage, premature birth or incidence of complications during the pregnancy term or while or during childbirth associated with Cannabis use.
The study also showed however, that three to four-year-old children were eventually negatively affected from mothers using Cannabis during their pregnancy. These negative effects included verbal and memory issues. Children whose mothers used marijuana while pregnant (during the first and second trimesters of pregnancy) were affected with short-term memory and verbal reasoning.
As these children who were exposed to Cannabis while in the womb grew older however, the results drastically changed. When these particular children became school age, they no longer had any memory deficits according to the Ottawa Prenatal Prospective Study. On the other hand, the Maternal Health Practices and Child Development study found that children appeared to have some short-term memory deficits associated with heavy Cannabis use during pregnancy the second trimester of pregnancy.
A very interesting thing about this study showed that the short-term memory deficits were countered by an increase in attention span when these children were compared with children who were not exposed to Cannabis while in the womb. Both of these studies confirmed that using Cannabis during pregnancy is associated with impaired cognitive function in children including attention deficits in executive function despite evidence showing that mothers who smoked Cannabis for morning sickness, depression or anxiety did not harm their children. Please note that recent animal research encourages caution when considering the use of Cannabis while pregnant.