Is It Safe to Drink Coffee During Pregnancy
Whether it is safe to drink coffee during pregnancy continues to be controversial. Some physicians believe that caffeine should be totally avoided and others believe in moderate consumption. What studies have shown is that caffeine does cross the placenta; caffeine stays in the system of pregnant women longer than it does in those of women who are not pregnant; and that the fetus does not have the necessary enzymes to break caffeine down and thus metabolism of the caffeine is slower.
The Food and Drug Administration (FDA) published recommendations in 1980 that advised pregnant women to limit or to avoid caffeine. The FDA study with rats found that one of five born to mother rats fed caffeine were born with birth defects. They had toes that were missing; delayed bone development; and in particular, the breastbone was developed late. Later studies did not identify these same deformities when women who drank coffee during pregnancy. It is important to note that there are differences in how caffeine is metabolizes in the body of a rat and the body of a human. The doses in the rats were higher than normal. If a human were to consume the same amount as was given the rat in the study, the human would have to drink up to 70 cups of coffee per day. An FDA study done later involving 12,000 women who were pregnant and who drank more than four cups a day had children that were low in birth weight and were born prematurely.
Since the 1980’s, there have been other studies done on the risk of miscarriage due to coffee during pregnancy. These studies have been bolstered by a new study done by Kaiser Permanente which showed that high caffeine amounts may increase the risk of miscarriage. This study was based on a group of caffeine consumers and also studied the impact of nausea and vomiting as well. The prior studies showed only there was a statistical risk and not a direct link. The new study tracked women from conception through miscarriage or delivery and was able to show a more causal relationship. Women from San Francisco were followed from October 1996 to October 1998. The women did not change the caffeine consumption habits because of the pregnancy. The findings indicate that women who took in up to 200 mg per day had a greater than 40% chance of risk to miscarry. Women who drank 200 mg or more had two times the risk of miscarriage. Women who had not smoked and had no history of prior miscarriage did have a higher risk when consuming high levels of caffeine.
An interventional study by the Dane, Bech and colleagues, found no link between drinking caffeinated beverages and early births and low birth weights. The study was a double blind, random trial. There was no correlation between mothers drinking a moderate amount of caffeine and mothers drinking beverages that were decaffeinated and the weight of the babies born. A group of 1,200 pregnant women who drank three cups a day were studied. They were 20 weeks pregnant when they joined the study group and were selected at random for drinking caffeinated or non-caffeinated drinks. Those assigned decaffeinated beverages consumed an average of 117 mg or the equivalent to three 12 oz sodas. The women assigned to drink caffeinated beverages consumed an average of 317 mg or approximately 2 ½ cups of coffee. The study found no significant differences in birth weight or length of gestation in the two groups. A later study by the same group found that drinking more than 9 cups of coffee per day increased the risk of still birth.
There was no correlation between consumption of caffeine and impact on the baby’s first year after birth. There have been numerous studies, yet the controversy remains. There is no real evidence and no clear proof that it is or is not safe during early pregnancy. If you feel you are a woman who is at high risk of complications during pregnancy you may want to avoid consuming caffeinated beverages. If you are not at high risk you can drink coffee during pregnancy in moderation and should experience no problems with a pre-term birth or low birth weight baby.