found this on the internet:
Is it safe to take Chinese medicine during pregnancy?
By Seah Ai Wei, TCM Physician
Thomson Chinese Medicine
This is a question often asked by first time mothers or those who have had experienced multiple miscarriages and are anxious to do everything possible to ensure a smooth pregnancy. One of the most common alternatives that surface during the quest is to take Chinese medicine, or what is popularly known as “安胎药” (An Tai Yao).
An Tai Yao refers to a group of prescriptions that have been specifically formulated to secure the womb. This is in line with the Traditional Chinese Medicine (TCM) belief that the womb, also called the “child’s palace” plays a primary role in nurturing the fetus. During the 10 months of pregnancy, the uterus also depends heavily on other organs to supply the “气”(Qi,vital energy), “血”(Xue, blood)and “精”(Jing, vital essence)via the Extra Meridians to nourish the uterus that provides nourishment for the fetus. Only when these organs and meridians are functioning well, then can the uterus work normally.
Over the thousands of years, many prescriptions have been formulated and the different treatment objectives include nourishing the Kidney (responsible for storing the vital essence), Spleen (that governs the blood), Liver (organ that stores blood), strengthening the vital energy (Qi), warming the uterus, clearing excessive heat, tonifying the blood etc. As a result, many concoctions were developed to meet the different needs and some like 寿胎丸(Shou Tai Wan)and 杜仲丸(Du Zhong Wan)are still prevalently used today.
It seems reasonable then to conclude that all mothers should consume An Tai Yao for the whole duration of pregnancy, or at least during the first trimester when the risks of miscarriage is higher. Following this line of thought, some might even make use of this period as an opportunity to devour ginseng and other tonics to strengthen one’s body and womb.
The truth however is this – women who are pregnant should be careful with ALL medication and this applies to Chinese medicine as well. Especially during the first trimester when the body is adapting to rising levels of hormones and many may be experiencing symptoms such as nausea, vomiting, sluggishness, fatigue, poor sleep and mood swings, taking tonics at this point will not help but may even aggravate the situation.
The guideline for taking Chinese medicine during pregnancy is this – it should not be taken as a prophylaxis (for preventive purposes) but as and when the situation warrants the use i.e. when there is a threat of miscarriage or if symptoms are severe and affecting the mother or baby’s well-being. The provison here is that you should stop using these herbs as soon as the symptoms go away. Even then, there is a long list of herbs that are contraindicated in pregnant women. Thus it is crucial that mothers-to-be do not randomly take these medicine but rather, under the strict supervision of a qualified physician.