Editor---Use of traditional Chinese medicines (TCMs) is increasingly common in western countries. Professor Ernst pointed out that herbal medicines including TCMs can cause adverse side effects.1 There were also concerns about the potential adverse fetal side effects following consumption of these agents during pregnancy.2 Because of the traditional beliefs that certain TCMs are beneficial to pregnancy, many paturients use TCMs during pregnancy.

We recently conducted a prospective survey regarding the use of TCMs during pregnancy in Hong Kong Chinese. In the 593 of 1,465 pregnant women who answered our questionnaire (40.5% response rate), 55.8% used TCMs during pregnancy. Women who used TCMs during pregnancy were more likely to be born in mainland China (67.1% vs 52.5%, p<0.01). They were also more likely coming from lower socioeconomic class, as reflected by the lower total family income, less educated, and the higher proportion of living in government housing estate. Of the 272 women responded to the question concerning the timing of their use of TCM during pregnancy, 174 (64.0%) reported continue consumption of TCMs after knowing that they were pregnant. Concerning the reasons for taking TCMs during pregnancy, 280 women gave 304 responses. The most common reason was ood for pregnancy and fetus?(n=126, 45.0%).

In our cohort of Hong Kong Chinese parturient, more than half had consumed TCMs during their pregnancy. This incidence is much higher than the reported figures of 9.1% in western countries.3 This is expected because the vast majority of population in Hong Kong are ethnic Chinese. Indeed many women continue to use TCMs despite knowing that they were pregnant. This indicates that they are not aware of the potential risk of TCMs. In fact, the most common reason for taking TCMs during pregnancy was ood for pregnancy and fetus?

It is important for health care providers to point out to pregnant women that the safety profile of many TCMs in pregnancy has not been established. TCMs may contain pharmacological active substances and may adulterate by heavy metals, both can have harmful effects on pregnancy. TCMs may also interact with western medicines which can cause serious consequences. In a population where the use of TCMs during pregnancy is very common, routine antenatal information should include use of TCMs in part of the history taking so to alert health care professionals. It is worthwhile for health care providers in western countries to note that some women are more likely to use TCMs during pregnancy (e.g. women born in mainland China) and more attention should be pay on this area. Further systemic research on the risks and benefits of specific TCMs in pregnancy would be of great clinical relevance.

References

1. Ernst E. Herbal medicine: where is the evidence. BMJ 2000;321:395-6.

2. Grange CS. Herbal medicines in pregnancy. bmj.com, 8 September 2000.

3. Gibson PS, Powrie R, Star J. Herbal and alternative medicine use during pregnancy: a cross sectional survey Obstet Gynecol 2001;97:S44-5.

From BMJ.com