During pregnancy, many chemicals must be avoided to prevent harm to the mother and unborn baby. Guarana is a common ingredient found in soft drinks and may be marketed as "natural" or "herbal." While guarana is a natural ingredient, it contains more caffeine than coffee beans, and mothers-to-be should exercise caution regarding its use.
Guarana derives from the seeds of a bushy plant, P. cupana, in South America. The seeds are ground and made into a paste, called guarana, which is used to flavor and caffeinate beverages. Caffeine is found in many plants, including the P. cupana, and acts as a defense mechanism against pests. Caffeine is the chemical found in plants, and guarana is a paste containing caffeine in its makeup. Guarana is higher in percentage of caffeine than a coffee bean, but the caffeine chemical is the same.
Caffeine stimulates the central nervous system, causing alertness, jitteriness, increased heart rate, dehydration and increased blood pressure. During pregnancy, caffeine can cross the placenta and enter the baby’s bloodstream, causing similar effects in the baby. However, according to the Department of Health and Human Services, low caffeine intake up to 150 mg or moderate intake up to 300 mg per day during pregnancy does not harm the baby. Therefore, a beverage or food containing guarana should be safe if it is below these thresholds. However, Drugs.com says guarana is contraindicated for pregnant women and breastfeeding mothers.
It’s long been believed that caffeine could cause infertility, miscarriages or birth defects. In a study by the Centers for Disease Control, there was no effect on fertility due to caffeine intake. Also noted is that caffeine, in any amount, does not cause birth defects. Miscarriages are harder to determine because of their frequency; however, the Organization of Teratology Information Specialists, OTIS, has determined that caffeine in low to moderate levels, 150 to 200 mg, does not cause miscarriages.
Despite findings that low to moderate caffeine may be safe, it’s important to know that an unborn baby’s body does not have fully functioning systems for breaking down and removing chemicals. Caffeine ingested by a pregnant woman may remain in her baby’s system for a longer period of time compared to the mother. Some babies born to mothers who ingested more than 500 mg per day of caffeine had faster heart and breathing rates, experienced tremors and were awake longer during the first days after birth. Guarana may be more likely to cause these effects because of its high caffeine content.
OTIS and the March of Dimes agree that a low amount of caffeine is considered to be 150 mg or less and high amounts are in excess of 300 mg per day. Regardless of what is a safe level of caffeine, it is recommended that pregnant woman be aware of their daily intake and try not to exceed 150 mg per day. Food or beverage labels saying they contain guarana should be used with caution. True guarana contains as much as double the amount of caffeine as an equivalent food item with a label stating "caffeine" as an ingredient.