Prenatal exposure to alcohol, drugs, and cigarettes all have an effect on the placenta, according to a new study.
Smoking cigarettes, drinking alcohol, and using drugs can cause development issues with the placenta in pregnant women.
Credit: Lucky Business/Shutterstock

Prenatal alcohol exposure (PAE) is known to be one of the most common preventable causes of developmental delays in the United States. Yet while animal studies have shown the adverse effects of PAE on placental development, few studies have examined these effects in humans. Until now.

Now, in the first study of its kind, researchers have found a link between prenatal exposure to cigarettes, drugs and alcohol, and the development of the human placenta. Yet another reason for expectant mamas to just say no!

For the study, researchers examined placentas from more than 100 pregnant women of mixed ancestry in Cape Town, South Africa. They interviewed 66 heavy drinkers and 37 non-drinkers about their alcohol, cigarette smoking, and drug use at three antenatal visits. They then evaluated the effects of prenatal exposure using placental size, structure, and the presence of infections and meconium.

The results?

Prenatal exposure to drugs, alcohol, and cigarette use all had an effect on the placenta. Alcohol exposure was related to lower placental weight and a smaller placenta-to-birth weight ratio. Methamphetamine use was associated with higher placental weight and a larger placenta-to-birth weight ratio. And marijuana was associated with larger placental weight.


In addition, alcohol exposure was shown to lead to an increased risk of placental hemorrhage. And both alcohol and cigarette smoking led to a decreased risk of intrauterine passing of meconium.

Pregnant women could obviously benefit from education on the potential side effects of using any of these vices during pregnancy.

But in the meantime, if you're currently pregnant or thinking about it, take these results to heart to keep you on the straight and narrow.

Hollee Actman Becker is a freelance writer, blogger, and a mom. Check out her website for more, and follow her on Twitter at @holleewoodworld.