Pregnancy and Caffeine: They Don't Mix

No questions about caffeine’s effect on health are more important than if and in what way caffeine affects fetal development.  Unfortunately, the issue about caffeine and pregnancy has been repeatedly beset with confusion, distortion, misinformation, and outright negligent inaccuracy.
The good news:  Researchers proved long ago that if a pregnant woman consumes caffeine, she does not risk producing a major teratology in her offspring.  This means, for example, that no child is going to be born with six fingers because his mother used caffeine during pregnancy.
The bad news:  There are a number of other critical health and developmental factors that must be considered in evaluating the safety or danger of using caffeine during pregnancy.
One salient fact is that pregnant women don’t metabolize caffeine the way others do.  The caffeine metabolism of pregnant women is dead slow, with a half-life of about 20 hours compared with about 3 hours for most people.  This slow half-life means that caffeine takes an extremely long time to be cleared from a preganant woman’s system.  This in turn means that when a women consumes any caffeine, she is bathing her fetus in the drug around the clock!
Caffeine has a profound effect on the adenosine system and on many, many other neurotransmitters.  It is therefore reasonable to assume that it could have a profoundly damaging effect on the development of the exquisitely sensitive fetal brain and nervous system.
Has this damage been proven?  No, it hasn’t.  But neither has it been studied very much! Nevertheless, one 1988 study showed that offspring of heavy caffeine using mothers had unusually high levels of irritability, jitteriness, and vomitting.   As things stand, however, if a teenager or young adult experiences problems controlling his temper or concentraiting or experiences mood swings or depression or mania, we wouldn’t be able to say if these pathologies traced back to caffeine use during pregnancy and might never even suspect it.
So, does caffeine hurt fetal development?  We don’t know.  But some studies have shown that 75% of infants have caffeine in their systems at birth.  Many of these infants are almost certainly born in a state of withdrawal from caffeine.  Even though such a condition has not been shown to be dangerous, do you really want your child to start life plagued with headaches, muscle aches, and increased tension?

Another confounding issue is the risk of miscarriages.  It has been shown that more than 300 milligrams of caffeine a day increases the chance of a miscarriage, whereas less caffeine does not increase this risk.  As a result, many misguided researchers advise that pregnant women can have up to three cups of coffee a day!  This advice is based on the antiquated idea that a cup of coffee contains 100 milligrams of caffeine.  This was true 50 years ago for what was then a typical 5 ounce serving of instant coffee.  Unfortunately, the typical 6 ounce filter drip cup of coffee today contains between 150 milligrams and 200 milligrams of caffeine.  Therefore, even two cups of such coffee would be approaching or exceeding the safe limit.
The bottom line:  Caffeine might not hurt your fetus.  But it might do serious harm.  Why take any risk at all of hurting your unborn child?  We recommend that pregnant women stay away from caffeine entirely – the way they should stay away from alcohol – and resume enjoying caffeine’s life-enhancing and energy boosting powers when they need them most, that is, after delivery, when they face the demands of caring for their newborn children.