Women hear a lot about things they can and cannot do while pregnant. There are a couple of misnomers (you can eat honey), there are a couple of absolute no’s (say goodbye to your beloved sushi), and there are some that are still up for debate.
There’s been a long-standing agreement amongst health professionals that coffee—and caffeine in general—should be avoided during pregnancy, but even after years of controversy, there are still conflicting ideas about moderate caffeine consumption, which is defined as about one 12-ounce cup of coffee per day, or less than 200 milligrams. To put this in perspective, one grande (16 oz) of Starbucks coffee has 330 milligrams; one 8-ounce cup brewed black tea has 47 milligrams
Excessive caffeine consumption (defined as drinking three or more cups of coffee or tea daily during the first trimester) has been also associated with a higher incidence of miscarriage and low birth weight. Plus just as it does in adults, caffeine can increase a baby’s heart rate. Also, because a fetus’ immature liver can’t rid itself of the caffeine as quickly as an adult liver, the caffeine may remain in the fetus’ bloodstream longer, and at higher levels. Research also shows that as a pregnancy progresses the body’s ability to break down caffeine slows (during the 2nd trimester it takes almost twice as long to clear caffeine from your bloodstream, and three times as long during the 3rd), which means you end up with a much higher level of it in your bloodstream. This is dangerous for you, and the fetus—who has no ability to process caffeine).
Beyond the above, caffeinated beverages contain compounds called phenols, which make it hard for your body to absorb iron. Many pregnant women are already iron deficient.
No matter what to find out what is right for you, talk to your doctor or healthcare provider. Moderate may make sense for you, but for women that are more at-risk, it definitely is not worth the sip.