Pregnancy Nutrition Concerns
Caffeine occurs naturally in coffee, tea, chocolate and cocoa. It is also added to soft-drinks, over the counter drugs, stay-awake medications and allergy medications. During pregnancy, changes occur to cause caffeine to be eliminated more slowly from your body than when you were not pregnant. Caffeine readily crosses the placenta and enters your baby's circulation.
Babies respond to caffeine by increasing heart rate. Heart rate changes were found with as low as 60mg caffeine (the equivalent of a cup of espresso) and 30 grams of dark chocolate. When the caffeine use stops, the heartbeat returns to normal. Caffeine is also associated with an increase of uterine contractions.
Despite these changes, research has failed to find any links between caffeine and miscarriage or poor fetal growth, birth defects and the normal development of children. One recent study found an association between intake of 200-300 mg of caffeine per day (2 to 4 cups depending on how it is brewed) and small for gestational age, but this study was observational which means it is only able to show a relationship and definitely not a cause effect.
What is the difference between a relationship and a cause and effect? It is possible the coffee (and the caffeine in the coffee) is responsible for the increased rates of small for gestational age. However, it is also possible that women who drink 200-300 mg of caffeine per day have other things in common that are not accounted for simply by the amount of coffee drank. For example, coffee is known to reduce appetite which may have an effect on the overall diet consumed. Overall research is not conclusive on any ill effects in pregnancy specifically from caffeine.
Research also suggests there are no behavioral or emotional changes in children whose mothers used caffeine during pregnancy. One study in Amsterdam followed a group of women and their children from pregnancy to see if caffeine played any role. They found no difference in risk for behavioral or emotional problems for children whose mothers used caffeine, even among women consuming the highest amounts of caffeine during pregnancy.
Until research is able to sort everything out, is is probably a good idea to limit your intake under 200 mg per day. A 5 ounce serving of coffee can have up to 100 mg of caffeine, while a 5 ounce serving of tea averages around 50 mg. Both drinks come available in caffeine free varieties. You can experiment to find caffeine-free flavors you like best. Next, consider soft drinks, which average about 36 mg of caffeine in a 12 ounce serving. Milk chocolate and cocoa have about 5 mg per serving, semisweet chocolate (the most popular kind for chocolate chip cookies) averages 20 mg per 1 once.
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