Researchers from Hong Kong have warned that women should be cautious about using the herbal remedy ginseng in the early stages of pregnancy after a study found abnormalities in rat embryos. They found that embryos exposed to more than 30 micrograms per millilitre of ginsenoside Rb1, one of the active ingredients in ginseng, had significantly lower morphological scores. Morphological scores are a way of assessing the development of the important organs of embryos: the higher the score, the more normal the development of the embryo.

Ginsenoside Rb1 is only one of the ginsenosides in commercially available ginseng. More than 20 had been identified and previous studies had shown that different ginsenosides might have different actions. Dr Louis Chan, a lead researcher, said that more studies were needed to evaluate the potential effects of other ginsenosides.

“Although results from animal studies may not reflect the circumstances in humans, our findings suggest that further investigations and monitoring of embryonic effects of ginsenoside on human pregnancy are warranted,” he said.

Ginseng, according to Dr Chan, is used to enhance stamina and the capacity to cope with fatigue and physical stress. It is also believed to have an anti-cancer function and to improve cognitive and physical performance.

Though the vast majority of herbal remedies available are safe and effective, it is important to remind women to use caution when using any herb – or drug – when pregnant.

European Society for Human Reproduction and Embryology, Sept 24, 2003