How much caffeine can you have while pregnant?

For women all over the world, some of the biggest questions after learning that they’re pregnant are how they have to alter daily routines to have a safe, healthy pregnancy. For many, daily routines start with rolling out of bed and fixing a mug of coffee. This is one habit that often has to be altered for pregnancy: The American College of Obstetricians and Gynecologists recommends that women do not exceed drinking 200 milligrams of caffeine per day while they’re pregnant, or two six-ounce cups of coffee each day. Here’s why it’s so important to keep maternal caffeine consumption under that threshold.

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How much caffeine can you have while you’re pregnant?

Daily caffeine intake for pregnant women should be less than 200 mg per day, according to the American College of Obstetricians and Gynecologists (ACOG). That’s the equivalent of one, 12-ounce cup of brewed coffee. This recommendation remains steady throughout an entire pregnancy regardless of trimester, though there may be an exception in the final trimester when the pregnancy is near full-term. In fact, the CDC recommends the same 200 mg caffeine limit for women who are breastfeeding.

“Organs are made by eight to 10 weeks [of pregnancy],” says Daniel Roshan, MD, a high-risk maternal-fetal OB-GYN at Rosh Maternal Fetal Medicine in New York. “That’s the key time. If someone’s baby is completely grown and ready to be delivered, there may be more potential for a woman to choose to drink more caffeine [at that point].” 

You should also take into account other common daily food and drinks, beyond coffee, that contain caffeine. “I need to inquire with a patient to understand how much caffeine they’re consuming before pregnancy between coffee and other beverages,” says Faina Gelman-Nisanov, MD, an OB-GYN at Maiden Lane Medical in New York. In order to savor that java drink every day, other foods containing caffeine need to be eliminated or balanced throughout pregnancy to stay below the recommended threshold.

It’s important to note, if you suddenly stop drinking caffeine when you become pregnant, you may experience symptoms such as headaches, migraine, nausea, fatigue, and drowsiness.

What food and drinks contain caffeine?

Coffee isn’t the only culprit in your pantry—and it’s not just caffeinated beverages. The most common food and drinks that contain various concentrations of caffeine are.

• Coffee: One 8-ounce cup of coffee brewed at home contains approximately 90 mg of caffeine, but the amount of caffeine varies depending on how you brew it. For example, an 8-ounce cup of coffee from Starbuck contains 160 mg of caffeine, while the same amount from McDonalds contains approximately 100 mg of caffeine.
• Decaf coffee: A cup of decaffeinated coffee contains only 2 mg of caffeine.
• Tea: A serving of black tea contains 47 mg of caffeine while green tea contains 28 mg.
• Soda: A 12-ounce bottle of dark cola contains 40 mg of caffeine. Other types of soft drinks, like Mountain Dew, contain 55 mg per 12-ounce serving.
• Energy drinks: One cup of an energy drink contains 85 mg of caffeine. If a serving is 16 ounces, that amount balloons to 170 mg.
• Energy shots: Concentrated energy shots contain high levels of caffeine—up to 200 mg per 2 oz serving.
• Chocolate: One ounce of dark chocolate has 24 mg of caffeine. Milk chocolate contains 6 mg.
• Caffeinated chewing gum: Caffeine content per piece of gum can vary; the amount has the potential to build quickly depending on how much gum a chewer uses daily.
• Coffee-flavored foods: While the milligrams per serving depends on the item, most foods or drinks that use coffee flavoring contain caffeine because it is extracted from coffee. Artificial coffee flavoring is generally caffeine-free.

Why is caffeine bad for pregnancy?

There are several reasons that physicians may recommend against caffeine during pregnancy. As a stimulant, caffeine affects your body in several ways:

• It increases heart rate
• It increases blood pressure
• It constricts blood vessels

If you’re drinking too much caffeine and not enough water, this could also lead to increased risk of dehydration. These effects of caffeine have the potential to restrict blood flow to the developing fetus and inhibit fetal growth when consumed in high amounts—though many physicians believe it does not cause a decrease in uterine blood flow or fetal oxygenation. 

A 2013 study from BMC Medicine found that maternal caffeine consumption was associated with low birth weights for babies, but not a lower gestational length that resulted in preterm births or higher risk of miscarriage. Studies on this topic are challenging because randomized, controlled studies of pregnant women are difficult or impossible to set up, caffeine intake is often self-reported (and may be inaccurate), and they do not account for the fact that women who consume coffee regularly may have some fundamental differences from women who don’t drink coffee. Additionally, they do not adjust for the impact of nausea during pregnancy, which is associated with lower miscarriage risk, and how that affects caffeine consumption.

Dr. Roshan agrees that there are flaws in various studies related to caffeine and pregnancy, saying, “The research has been really controversial…I’ve been practicing for 20 years and epidemiology studies are not accurate because they put everybody into one basket.” Meaning, it’s very hard to tease out whether caffeine itself caused the medical problems the studies report or if the behaviors related to too much caffeine, like lack of appetite, and not the caffeine itself resulted in pregnant women eating less, decreased weight gain, and having lower birth weights. Or, if another behavioral factor or pre-existing medical issue is at play.

What happens when you drink too much caffeine while pregnant?

If an expectant mother realizes that they exceeded the recommended daily caffeine intake while pregnant, the first thing to do is get in touch with a healthcare provider. A provider can administer anatomy scans to ensure that fetal growth is on track and examine how prenatal organs are developing. Then, schedule follow-ups every two to three weeks to ensure that the fetus is growing on schedule. By 28 weeks, the fetus should be 2.5 pounds. From there, the goal is for the fetus to gain half a pound on average per week until term.

 The key part of the pregnancy time frame, Dr. Roshan and Dr. Gelman-Nisanov agree, is between weeks eight to 10 when a fetus’s organs and nervous system are developing. That’s when a fetus would be more sensitive to maternal caffeine consumption.

The bottom line – caffeine while pregnant is safe in moderation

Too much caffeine may lead to negative outcomes for developing fetuses. However, Dr. Roshan and Dr. Gelman-Nisanov stand by moderate caffeine consumption. Meaning, sticking to the general recommendation for 200 mg of caffeine per day is considered low risk.

“Until we have good studies that truly attribute these things to caffeine and not behavior, we have to continue with what we’re doing and not make the pregnant woman’s life miserable,” Dr. Roshan says. Follow the guidelines and stick with moderation, unless your provider advises you otherwise.