Less is better with caffeine and energy drinks during pregnancy, says expert

Millions of people drink coffee, soda, and/or tea daily, making caffeinated beverages the most commonly consumed stimulants in the world. Highly caffeinated energy drinks also have been a hugely popular pick-me-up for more than two decades, especially among younger adults and teens.

But pregnant individuals should be careful regarding energy drinks and their overall intake of caffeine, according to an expert at UT Southwestern Medical Center.

"Energy drinks contain varying amounts of caffeine, so check nutrition labels to understand how much caffeine and other ingredients they contain," said David B. Nelson, M.D., Associate Professor of Obstetrics and Gynecology and Division Chief of Maternal-Fetal Medicine.

National guidelines recommend moderate caffeine consumption of less than 200 milligrams per day for anyone pregnant or attempting to become pregnant. The American College of Obstetricians and Gynecologists says that level does not appear to be associated with miscarriage or preterm birth, but the relationship between caffeine consumption and fetal-growth restriction remains uncertain.

The caffeine content in energy drinks ranges from 50 mg to 500 mg in cans or bottles that vary in size from 8 ounces to 24 ounces. An 8-ounce cup of full-strength coffee contains just under 100 mg of caffeine, and the amount in sodas varies widely. For instance, a 12-ounce Coke has about 34 mg of caffeine, Diet Coke has 46 mg, and a regular Mountain Dew has 54 mg.

Small energy shots, usually sold at 2 fluid ounces, contain particularly high levels of caffeine—about 200 mg. Regulation of energy drinks, including content labeling and health warnings, differs globally, but the U.S. has some of the most lax requirements. The Food and Drug Administration doesn't regulate energy drinks, which are generally marketed as dietary supplements or conventional beverages.

The question of whether adverse pregnancy outcomes are related to caffeine is somewhat controversial, according to the latest edition of Williams Obstetrics, which reported that heavy consumption (about 500 mg daily) slightly raises the risk of miscarriage. Studies involving moderate intake—less than 200 milligrams daily—have not identified a higher risk. A recent study of patients from 10 states found that pre-pregnancy or first-trimester daily caffeine consumption was not strongly linked to birth defects.

Dr. Nelson said it can be difficult to curb intake of caffeine, and doing so can cause withdrawal symptoms including headache, fatigue and drowsiness, decreased alertness, depressed mood, irritability, and trouble concentrating.

"Gradual reduction in caffeine intake over several weeks before planning pregnancy, or when you find out you are pregnant, can help prevent caffeine withdrawal," said Dr. Nelson, a Dedman Family Scholar in Clinical Care.

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