Pregnancy effects of 4 drugs, including marijuana

Various studies have found an association between heavy marijuana use in pregnancy and things like lower tests scores, increased depression and impulsive behavior in teenagers. (Sharon Steinmann)

This story is part of a package produced in collaboration with ProPublica and includes reporting by ProPublica's Nina Martin and AL.com's Amy Yurkanin. Read When the womb is a crime scene
How do these different drugs effect the health of women and babies?

Drug: Benzodiazepines
Science: Though used for decades to treat pregnancy-related anxiety and hypertension (preeclampsia), benzos have never been tested directly on pregnant and breastfeeding women to determine the effects on the fetus and infant. Diazepam (Valium) is considered the safest form to take in pregnancy, ideally in very small amounts.

Pregnancy Effects: Some studies point to a slightly increased risk of congenital anomalies such as cleft palate; others do not. The FDA classifies benzos as Category D drugs (positive evidence of human fetal risk; benefits may outweigh risks), to be avoided in the first trimester.

Birth Effects: Newborns exposed to acute doses in the third trimester or smaller doses over longer periods can have withdrawal symptoms that include floppy limbs, lethargy, and difficulties feeding and sleeping.
Long-term Effects: Babies born with withdrawal symptoms don't appear to suffer any lasting effects.

Drug: Marijuana Science: For ethical reasons, it's been almost impossible to conduct clinical trials in the U.S. that expose pregnant women to marijuana, so many published studies have relied on historical and retrospective data from other countries. New, more potent strains make it harder to understand the drug's true effects.

Pregnancy Effects: Pot has been used in other cultures for thousands of years to treat pregnancy-related conditions from morning sickness to labor pains. Studies of mothers in Jamaica and elsewhere have found no link to miscarriage or birth defects.

Birth Effects: While some studies have reported associations between marijuana and low birth weight, particularly in women who use it late in pregnancy, other research has found that the effects are insignificant when factors such as maternal age and tobacco use are taken into account.

Long-term effects: Various studies have found an association between heavy marijuana use in pregnancy and things like lower tests scores, increased depression and impulsive behavior in teenagers. But children in these studies are often poor, with prenatal exposure to multiple substances, making it difficult to link their outcomes to a particular cause.

Drug: Cocaine
Science: Researchers have been tracking "crack babies" through childhood and adulthood for nearly 35 years, upending many early assumptions about the drug's short- and long-term effects.

Pregnancy Effects: Heavy cocaine use has been associated with an elevated risk of preterm birth, miscarriage and placental abruption (when the placenta pulls away from the uterus, causing catastrophic bleeding). But early reports of widespread birth defects, including heart and gastric abnormalities and limb deformities, have not been supported by later research.

Birth Effects: While some cocaine-exposed newborns exhibit symptoms such as irritability, hyperactivity, and high-pitched crying, studies have found that most do not. Some effects once blamed on the drug, such as low birth weight, may be caused by nicotine, alcohol, or a lack of prenatal care.

Long-Term Effects: Early reports predicted that people who'd been exposed to crack in utero would suffer from severe emotional, mental, and physical disabilities. But those fears turned out to be overstated. Some studies have found that prenatal cocaine exposure increases the risk of cognitive and behavioral problems in children and teenagers, but not to the degree once thought — and underlying factors such as poverty, malnutrition, and poor-quality education appear to be much more influential.

Drug: Methamphetamine
Science: Research on neonatal and developmental effects has been hampered by small sample sizes and the tendency of subjects to use multiple substances. To understand the drug's long-term effects, the Infant Development, Environmental, and Lifestyle (IDEAL) study is following children in four states over a number of years.

Pregnancy Effects: Some research suggests that the drug can restrict the flow of nutrients and oxygen to the developing fetus, inhibiting growth and increasing the risk of placental tearing and premature delivery. Depression — itself a risk factor for poor pregnancy outcomes — is highly correlated with meth use.

Birth Effects: Meth-exposed newborns may be smaller than normal and sometimes display signs of lethargy or stress.

Long-term Effects: One IDEAL paper suggests that children exposed in utero may be at slightly higher risk for deficits in fine-motor function, but these seem to disappear over time. Other studies have found an increase in cognitive, mood and behavior problems in young children.