I found some interesting information on caffeine use. In a study done with 16 women who consumed more than 600 mg of caffeine daily, five delivered stillborn babies, eight spontaneously aborted, two delivered prematurely, and one achieved a normal pregnancy and delivery. (Source: Nutrition in Pregnancy and Lactation, Fifth Edition, By Bonnie Worthington-Roberts and Sue Rodwell Williams. The authors got the information about the 16 women from a study by Weathersbee PS, Olsen LK, Lodge JR: Caffeine and pregnancy: a retrospective survey, Postgrad Med 62:64, 1977.)

Another study with women consuming moderate to heavy amounts (150mg/day) are more likely to experience late first and second trimester spontaneous abortions (miscarriage) compared to women who consume less than 150mg daily.

Consuming 300mg or more is considered heavy usage, and those women are 50% more likely to spontaneously abort. The reason it can cause spontaneous abortion is that caffeine may alter the blood flow to the placenta. Another side effect with the decrease of blood flow is that the baby is not receiving all the nourishment it needs. That results in growth retardation and low birth weight. Caffeine consumption of 300mg or more increases the risk of having a low birth weight baby, and may cause a reduction in head circumference as well. 300mg is equal three, 5-ounce cups of coffee. (Source: Weathersbee PS, Lodge JR: Alcohol, caffeine and nicotine as factors in pregnancy, Postgrad Med 66:165, 1979.)

After birth, there is a potential for problems, too: In a recent study published in the Archives of Disease in Childhood, researchers from New Zealand reported that children of women who consumed 400 milligrams of caffeine a day were more than twice as likely to die of SIDS. The research team from Community Child and Family Service in Christchurch, New Zealand, explains that caffeine's stimulant effect may leave the baby "with an inadequate respiratory drive." The authors also stress, "The importance of this (study) finding is that drinking coffee, tea, and cola is a common and easily modifiable behavior. Mothers, therefore, have the opportunity to alter this risk factor." (Measures used: 1 cup coffee: 100 mg, 1 cup tea: 40mg, 1 cola: 40mg)

Keep in mind there are other lifestyle factors that play a role. Studies show that women who consume high amounts of caffeine also tend to smoke. If your wife is a smoker, that will also affect the outcome of her pregnancy. If she is not going to cut out her caffeine completely, ask her to cut it down to no more than 300mg/day. If she is worried about having withdrawal effects, suggest she gradually cut down, maybe combine decaf coffee and regular, then gradually cut down the amount of regular in the mixture.

Consuming large amounts of caffeine does not mean your wife will have a miscarriage or that your baby will die of SIDS, but it increases the chances greatly! The studies show the possibility is there, but everyone is chemically different, and many women may not have any problems -- but that is not to say she won't. I think she should take these significant risk factors into account.

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