In addition to being used in traditional Chinese medicine, there are more and more herbs used in general diets or nutritional supplements, such as green tea extracts, turmeric, etc. These well-known ingredients are all belong to the category of herbs. Generally speaking in terms of Western medicine, it’s actually less recommended for pregnant women to use ingredients containing herbal extracts, because many ingredients have not been approved by the FDA and have not been tested for safety in pregnancy. Therefore, it would be better to avoid the use of herbal products in diets or supplements during pregnancy in order to prevent potential safety hazards. Moreover, the manufacturer's extraction and processing technology will affect the purity of the back end and whether there are other residual components. In other words, even the same herb may have different qualities from different raw material suppliers.
Although herbs are natural, they are not necessarily safe for pregnant women. Recommended by the FDA in the U.S., it is best to consult a physician or someone professionally trained in medical fields before taking any herbal ingredients during pregnancy. Because some herbs contain ingredients that may increase the risk of miscarriage, preterm labour, stimulate uterus, or they may be harmful to your baby during pregnancy. For the same herb, different parts may have different efficacy or different risks. In Taiwan, the Ministry of Health and Welfare have compiled a list of different parts of herbs as regulations. Some herbs may be safe in the daily diet; however, taking in large amounts or consuming high concentrations of extracts directly could be dangerous.
Herbs commonly found in diets or dietary supplements include：
Turmeric itself has good anti-inflammatory effects. In food, curries also contain turmeric, but they have been recognized as generally safe due to the low content. However, for the turmeric extracts (curcumin) in dietary supplements, because of its high concentration, experts usually recommend to avoid it during pregnancy generally. Because curcumin has not been tested for safety in pregnancy clinically, and excessive doses may lead to the potential risk of premature birth or miscarriage.
Rosemary is also a widely used herb in food. For the solid rosemary leaves used as a spice in the diet, it is safe to eat due to small amounts. However, once rosemary is extracted and used as an additive in dietary supplements or medicine, it is not good for pregnant women.
The American Pregnancy Association indicated that rosemary extracts in high concentrations or in medicinal doses can cause uterine irritation; thus, pregnant women are advised to avoid rosemary extracts. Two studies pointed to the potential hormonal effects of rosemary extracts (Lemonica., 1996; Zhu et al., 1998); the preliminary evidence showed that it can be embryotoxic, and it has been traditionally used as abortion pills. Therefore, pregnant women or women who are planning to conceive are advised not to take this ingredient. Besides, patients who are at risk of iron deficiency should also avoid rosemary because it can reduce iron absorption (Samman et al., 2001).
In addition, people with coagulation-related disorders or taking anticoagulants, or those who anticipate surgery should also be aware that rosemary extract may increase the risk of bleeding due to its anticoagulant properties (Yamamoto et al. , 2006).
However, due to its antioxidant properties, rosemary extracts are often added to fish oil products as an antioxidant to avoid fish oil oxidation in foreign countries. Anyhow, it is recommended to avoid it as much as possible during pregnancy. Therefore, if pregnant women choose common dietary supplements in the form of "soft capsules", such as fish oil, lutein, etc., please remember to check carefully whether they contain rosemary extract to prevent accidental Ingestions.
Ginger is another common ingredient used in our diet; as a spice, it’s safe with small amounts. In fact, ginger has been shown to relieve symptoms of nausea and vomiting while pregnant. Therefore, ginger has been used in some maternal dietary supplements to reduce the discomfort during pregnancy. Nausea and vomiting of pregnancy affects approximately 80-90% of pregnant women, the only difference is the degree of discomfort. Most pregnant women experience both symptoms at the same time, a few of them have nausea without vomiting or retching, and very few experience only vomiting. It typically begins around week 4-9 of pregnancy, these symptoms get worst around week 7-12, and gradually decreases after week 16. About 15-30% of pregnant women continually experience the sickness until 20 weeks, or even before delivery.
Some published studies have shown that giving pregnant women one gram of fresh ginger per day for four consecutive days could be helpful in reducing nausea and vomiting. In 2012, a study published by Plengsuriyakarn et al. indicated that a large dose of 5 grams per kilogram of body weight of ginger is still considered as safe and non-toxic. However, some experts pointed out that excessive consumption of ginger may be unsafe and advised to stop eating, especially for pregnant women who are about to give birth. Pregnant women who have had miscarriage, vaginal bleeding, or coagulation-related conditions are specially recommended not to eat ginger for the time being. Because high concentrations of ginger powder may increase the risk of bleeding due to the blood clotting reduction effects, especially when taking in with other herbs or medicines that have the same effect, the power will be enhanced.
All in all, ginger is generally a safe ingredient for pregnant women, and many studies have confirmed that the daily consumption of ginger (ginger tea, ginger supplements, etc.) within 1000 mg is safe, and it can reduce the discomfort of pregnancy. However, if you want to take in large amounts of ginger powder, extracts or ginger tea, or if you have had a special medical history or condition during pregnancy, it is recommended to consult your obstetrician or medical professional before use.
Ginkgo/ Ginkgo Biloba：
In traditional medicine, Ginkgoa is a well-established medicinal plant. Ginkgo is commonly used in oral nutritional products as well; there are even chewing gums containing ginkgo on the market in Japan. However, in Taiwan's regulations, ginkgo biloba extract is listed as a medicinal ingredient and cannot be used in food. Only ginkgo fruit can be added to food. Ginkgo biloba is generally considered to have many phytochemicals, has antioxidant capacity and has been used to improve memory function, but this part of the effect is still questioned by many experts.
As for pregnant women, it is recommended not to take the ingredients contain ginkgo, especially those who are about to give birth. Because ginkgo may have anti-platelet properties, it may prolong the time and risk of bleeding. Even for ordinary people, if you're planning to have surgery, stop taking ginkgo beforehand. During lactation the safety of ginkgo is still unknown, so it’s better not to use ginkgo at all as recommendation.
Other common herbs to avoid while trying to conceive, during pregnancy, and lactation include : North American Black Cohosh, Blue Cohosh, Saw Palmetto, Goldenseal, Ephedra, Yohimbe, Pay D' Arco, Passion Flower, Roman Chamomile, Pennyroyal and Aloe.
During the time of trying to conceive, pregnancy, and lactation have certain needs for basic nutrients, including B vitamins, Omega-3, iron, calcium, zinc, and lutein. However, if you want to take herbal-related ingredients, it is recommended that you consult your obstetrician, physician or professionally-trained medical staffs before using to ensure the safety.