The next article in STAT’s “The Deadliest Drug” series focuses on alcohol use during pregnancy.

The main point: After precipitous declines in the last 50 years, rates of alcohol use during pregnancy in the U.S. started climbing a decade ago.

• Why it’s important: Prenatal exposure to alcohol can cause a wide range of negative health and neurodevelopmental conditions, including fetal alcohol spectrum disorders (FASDs).

The numbers:

• More than 1 in 8 pregnant adults in the U.S. reported drinking in the past month, making alcohol use a more common phenomenon than gestational diabetes. Of those who drank, a quarter reported binge drinking.
• The prevalence of FASDs is difficult to measure, but the most recent federally funded community studies have found as many as 1 in 20 school-aged children may have a disorder caused by prenatal alcohol exposure.

The bigger picture: At a time when federal health officials are expressing alarm on issues such as infertility, neurodevelopmental disorders, and addiction, they have placed little emphasis on the potential harms of drinking during pregnancy.

• Lack of data: The Trump administration has hampered key data collection efforts that track alcohol use, including during pregnancy and postpartum (e.g., Pregnancy Risk Assessment Monitoring System (PRAMS) data). The wide range of harms from alcohol use during pregnancy is known, but just how much alcohol can cause them is unknown.
• Questioning advice: Experts worry that Americans are questioning the conventional medical advice of avoiding all alcohol while pregnant.
• Insufficient education for health care providers: Some parents are being told even by their health providers that light-to-moderate drinking is okay during pregnancy. While about 80% of pregnant women in the U.S. reported being screened for alcohol use, only about 16% who said they drank in the previous month received advice to stop drinking or cut back. A 2019 survey of over 500 midwives, nurses, and nurse practitioners in the U.S. found that nearly 40% believed alcohol was safe to use during at least one trimester.
• Increased drinking among women: Over 5 million adult women report drinking heavily, and more than 40% of pregnancies in the U.S. are unplanned. Rates of prenatal care in the first trimester have dropped. Even if a large share of parents quit drinking once they know they are pregnant, it may be too late to avoid impacts. It remains to be seen how heavier drinking by non-pregnant women in recent years will translate to more drinking during pregnancy.
• Unclear diagnostic criteria: There is no single accepted diagnostic tool for FASDs and no easy biomarker. Many with FASDs go unidentified or are misdiagnosed with other conditions.