Research has shown a strong relationship between alcohol and miscarriages. A 1977 study found that women who have a drink every day have a risk of miscarriage 2.5 times higher than non drinkers (N Engl J Med, 1977; 297: 793-6). In this same study, they found that, if the woman was a drinker and a smoker, her risk of having a miscarriage increased by up to four times.
The conclusion from a number of studies on women is that even moderate alcohol consumption works as a reproductive toxin and, as such, can increase the risk of a miscarriage (Lancet, 1980; ii: 176-80).
Caffeine is a stimulant and could therefore be classed as a drug. It has an adverse effect on fertility, and can also cause problems once a woman is pregnant. In a study of 2967 pregnant women, carried out by the Department of Epidemiology and Public Health at Yale University School of Medicine, the researchers found that drinking three or more cups of tea or coffee a day was associated with an increased risk of miscarriage (Am J Epidemiol, 1996; 144: 989-96). Other research has shown that caffeine during pregnancy can increase the probability of chromosomal abnormalities which could lead to a miscarriage.
Since 1980, the US Food and Drug Administration has advised pregnant women to minimise their caffeine intake, citing the dangers of possible miscarriages or having a mentally retarded baby. Some studies suggest that there is a doubly increased risk of fetal loss when as little as one to three cups of coffee are consumed a day. So, the logical advice is to err on the side of caution and avoid caffeine altogether, especially if you have a history of recurrent miscarriages (JAMA, 1993; 270: 2940-3).
Even decaffeinated coffee has been linked to an increased risk of miscarriage (Am J Epidemiol, 1996; 143: 525, abstract no 99) since there is still some caffeine left, even after most of it has been removed. More over, decaffeinated coffee contains two other stimulants theobromine and theophylline which are not removed when coffee is decaffeinated. Also, most decaffeinated coffee has been decaffeinated by a chemical which can remain in the product. An important point to remember is that caffeine comes in many other forms besides tea and coffee. It is there in colas and other soft drinks, as well as in chocolate and pain relieving medications such as headache remedies.
Much fertility treatment involves boosting this or that hormone often by excessive amounts to 'trick' the body. In the case of miscarriages, the doctors may suspect an inadequate level of progesterone or too high a level of LH, and so will use drugs to try to rectify the imbalance. But as with any drug, the treatment will have its own side effects and repercussions. On the other hand, by giving your body the right nutrients, minimising environmental hazards and getting into optimal health, you and your partner can do a great deal to help prevent another miscarriage or one happening in the first place.
Marilyn Glenville's latest book is Natural Solutions to Infertility (Piatkus, 2000, £10.99). She has also given many lectures and workshops on natural menopause. The next workshops will be held in London on 1 July, in Ireland on 2 July, and in Manchester on 8 July. Call 08700 715 715 for details.