Herbal Supplements in Pregnancy Botanical dietary supplements or herb
Botanical dietary supplements or herbal supplements have become commonly consumed by the American public including pregnant and breast-feeding women. The annual sales exceed several billion dollars per year. Rarely are physicians or pharmacists involved in a patient's decision to use herbal supplements. Moreover, patients frequently do not tell their healthcare providers that they are using herbal products. This may be because they forget or do not really think of herbs as drugs or because they do not want to incur their doctors’ disapproval for taking herbal products.
Many women believe that because they are "natural products" they are safer than drugs. Natural is not synonymous with safe and excellent examples of that are natural products such as arsenic, Hemlock and cyanide.
A big difference between herbs and approved drugs is their regulatory status. In order to be sold as drugs, either by prescription or OTC (over-the-counter), products must meet strict requirements. The ingredients must be identified and must be proven safe and effective. A few herbs that have met these requirements are now sold as OTC drugs such as senna, cascara, and psyllium. Most herbs are sold as dietary supplements under the Dietary Supplement Health and Education Act of 1994. Under this law, supplements are considered safe unless proven UNSAFE by the FDA. This is in contrast to prescription drugs which must be proven safe and effective by the manufacturers prior to marketing. Unfortunately, the FDA does not have the manpower to evaluate all supplements in order to determine if they are UNSAFE.
Herbal products can interact with prescription drugs. Just as there are drug-drug interactions, there are herb-drug interactions that can either increase or decrease the effectiveness or toxicity of either the herb or the drug.
People are often confused when they see the following words printed on a dietary supplement label: "This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure or prevent any disease." This statement is required by the dietary supplement law to go along with the manufacturers’ claims. Therefore, it is a standard statement on all dietary supplement products.
Even though some herbs have been available for thousands of years, little is known about their effects on eggs, sperm, embryos, fetuses, newborns or the nursing infant. Moreover, as unregulated products, the concentration and content and presence of contaminants for most herbal products has not been evaluated. Natural products will naturally have multiple chemical compounds in addition to the compound of interest in that supplement. There is also the potential for the plant to have been exposed to herbicides or pesticides and generally testing is not performed for these contaminants.
One of the 2 key factors that determines if a supplement may have risk for developmental toxicity including abnormal growth, structural abnormalities, functional and/or neurobehavioral deficits is dose and this is rarely indicated in reports on herbal supplements. The second key factor is what is the major component of the herbal supplement and what are the other natural products associated with the major component. Herbal products never contain a single product but instead are a mixture of related products. This makes it difficult to evaluate the toxicity of an herbal supplement but is also possibly why some herbal supplements are effective when the studies are performed with the natural product but not effective when the single compound of interest is evaluated. This is also a major problem when evaluating traditional Chinese medicine. Most Chinese herbal products are combinations of multiple herbs and not just a single product which makes testing for efficacy and safety difficult. In traditional Chinese medicine, combinations of drugs are frequently used which may be more effective than the individual components.
Ten Herbs to Never Use during Pregnancy!
There are 10 herbs that are should be considered contraindicated in pregnancy and include aloe, Arnica, blue cohosh, chaste berry, dong quai, feverfew, goldenseal, Salvia divinorum, valerian, and passionflower.
Aloe. People use aloe to treat burns, sunburns, scald psoriasis, eczema and stings and skin abrasions. It has also been used orally as a laxative. Although most authorities agree that fresh aloe gel from the plant has some wound healing activity, this activity might not be present when the gel is stored as a lotion or topical gel. Although oral aloe has been used for centuries as a drastic cathartic, it can cause severe abdominal cramping, diarrhea and profound fluid and electrolyte imbalances, and therefore should never be used as a laxative. Oral aloe can also cause uterine contractions and lead to an abortion. If aloe is applied in small amounts topically, it is probably safe to use during pregnancy.
Arnica. The dried flowers and sometimes the roots and dry zones, are the parts of this perennial plant that are used topically for their anti-inflammatory and analgesic effects. Occasional topical use probably represents a very low risk, but absorption may occur when it is widely applied or is applied to broken skin. The FDA has classified Arnica as an unsafe herb and when used oral only it is considered a poison. It is a uterine stimulant and an abortifacient.
Blue cohosh. Some of the components of this herb have been shown to be teratogenic and toxic in various animal species; therefore, it should be avoided in the first trimester in women. The herb has uterine stimulant properties that are used by nurse midwives to stimulate labor. There is some evidence that there may be some potential fetal and newborn toxicity and therefore it should be used with caution.
Chasteberry (Vitex agnus-castus). People have used chasteberry to treat menstrual cycle disorders and as an ovarian stimulant. It has been shown to inhibit the release of prolactin and there are reports showing effects on gonadotropin release as well. Progesterone and hydroxyprogesterone have been isolated from the leaves and flowers of the chasteberry tree. Chasteberry should not be used by women who might get pregnant, since it has potential to cause disruption in the ovarian cycle and possibly even miscarriage.
Dong quai. This has been used for centuries in Chinese medicine to treat various menstrual problems including dysmenorrhea, amenorrhea, and menopausal symptoms. Animal studies have shown uterine tonic effects and therefore should not be used during pregnancy.
Feverfew. This herb has been used for labor induction, menstrual disorders, potential miscarriage, morning sickness and as an abortifacient. Because of its antipyretic properties, it has been known as “medieval aspirin.” One of the more common uses is for migraine headaches and there are medical studies documenting its efficacy at decreasing the frequency and severity of migraine headaches.
Goldenseal. People use goldenseal to treat mucous membrane infections caused by bacteria, fungus, and protozoa. These are infections commonly found in the mouth, respiratory, gastrointestinal and genitourinary tracts. Goldenseal also has stimulatory effect on involuntary muscles probably through an oxytoxic effect in the intestinal tract and uterus. For that reason, goldenseal is contraindicated in pregnancy.
Salvia divinorum. This herb has hallucinogenic effects and is used in certain regions of Mexico for healing and religious rituals. The herb is either smoked or chewed. When taken orally, systemic effects are dependent upon absorption across the oral mucosa as the active ingredient is destroyed in the GI tract.
Valerian. A large number of preparations containing valerian are available over-the-counter. It has been used as a sedative and hypnotic for anxiety, restlessness, and sleep disturbances. Because of the risk of cytotoxicity in the fetus and hepatotoxicity in the mother, this herb should be avoided during pregnancy; however, there are no reports of its use during pregnancy to verify these risks.
Passionflower. This name refers to about 400 species of the genus Passiflora. It is available in both oral and topical forms and is used for nervousness, neuralgia, insomnia, pain, asthma, seizures, burns, hemorrhoids, and menopausal complaints. The herbal products contain a large number of chemicals, none of which have undergone reproductive testing; however, because it has uterine stimulant properties, the oral formulation is best avoided in pregnancy.
Herbs Possibly Safe in Pregnancy?
There are 14 other herbs that when used in small and infrequent doses probably cause no harm to the mother, embryo, fetus or newborn.
Chamomile. Often times used for gastrointestinal disturbances including spasms and nausea. Excessive use of this herbs should be avoided because it is thought to have uterine stimulant and abortifacient properties. Although controversial, some nurse midwives prescribed chamomile teas for the treatment of morning sickness. Because the plant sources contain coumarin compounds, ingesting chamomile by women with coagulation disorders could be a concern. Nevertheless, this herb has been used for thousands of years by pregnant women and at least with the occasional use, the risk of harm must be very low. There are no reports of teratogenicity.
Echinacea. This herb is used topically to enhance wound healing and orally as an immunostimulant. In Germany an IV formula is also used as an immunostimulant. It has been used as a "broad-spectrum" immune system stimulator and has been recommended to assist in the prevention or treatment of viral upper respiratory tract infections. The roots and the leaves contain the most potent immunostimulating components. There are many active constituents in Echinacea, and they vary depending on the species and the part of the plant that is used. Because it is immunostimulatory, there is a relative contraindication to use in persons with autoimmune diseases, lupus, multiple sclerosis, AIDS and HIV.
Evening primrose oil. This oil contains primarily two essential fatty acids, cis-linoleic and gamma-linolenic acid. These polyunsaturated fatty acids are easily oxidized and degraded; therefore if the oil has a rancid smell or bitter taste it has not been properly processed and/or protected. Fresh oil has a clean smell and taste. It is commonly used by nurse midwives for the induction of labor. It has not been used as an abortifacient but could have this property as well at high doses. No adverse effects have been reported in fetuses or newborns from its use. The doses vary widely and include both oral and vaginal routes of administration.
Garlic. Garlic has been used for food flavoring since ancient times and it appears to be safe during pregnancy. Very high doses have the potential to induce uterine contractions but no adverse effects from this have been reported. It is most common uses are to reduce cholesterol and lower blood pressure. Historically it has been used as a "broad-spectrum" antimicrobial agent for bacterial, fungal, viral, and parasitic infections. The effectiveness for these indications is controversial but there are studies that do demonstrate these benefits. The only significant side effects seem to be the offensive odor of garlic that can be detected in the breath and perspiration of people who use it regularly in significant quantities.
Ginger. There are no reports of ginger inducing toxicity in pregnancy. It is used widely as an antiemetic for morning sickness and motion sickness. Pregnant women taking a dose of 250 mg powdered ginger root 4 times daily experienced a significant reduction in the severity of nausea and the number of vomiting attacks. Galanolactone, one of the constituents of ginger, has been shown to possess activity as a 5-HT3 antagonist. Zofran and other antiemetic drugs are manufactured 5-HT3 antagonists.
Ginseng. The root is the most important part of this plan and has been used in medicine for more than 2000 years. It has been promoted for multiple pharmacologic effects including CNS, cardiovascular, endocrine, antineoplastic and immunomodulatory effects. Many people use ginseng to increase their endurance and to fight off fatigue. Hypertension and hypoglycemia have been reported in nonpregnant patients but there is insufficient data in pregnant patients. There is 1 brief study from 1991 that compared 88 women who took the herb during pregnancy with 88 controls. There were no differences with regards to the pregnancy outcomes in this study. Many ginseng products have been shown to be adulterated and therefore not only does the amount of active ingredients vary but there often times are entirely different ingredients. Ephedrine and caffeine are sometimes added to ginseng products to give patients the energized feeling that they desire. Because of the concerns of adulterated ginseng products, ginseng should not be encouraged in pregnancy. Siberian ginseng is a completely different plant than Chinese or Korean ginseng (Panex ginseng) and there is no information on use in pregnant women.
Ginkgo biloba. There are several animal reproduction studies that suggest a low risk, but there is no reported human pregnancy experience. It is an ancient herbal preparation that has been used for organic brain syndrome, circulatory disorders, asthma, vertigo and tinnitus. These effects are all probably a consequence of increased blood flow to the brain. Because it has been used extensively in Asian countries for many years, it is doubtful that any major teratogenic effect would have been unnoticed but there may be more subtle or low incidence toxic effects that have not been previously detected. Ginkgo leaf extract is the common means of use with the usual dose standardized to 120 to 160 mg daily. Ginkgo seeds and fruit pulp are toxic if ingested. The ginkgo species was almost destroyed during the Ice Age, but it survived in China and today it is grown on plantation throughout the world including the United States for pharmaceutical purposes.
Kudzu. Although there is no human or animal data regarding pregnancy, this herb has been used for more than 2500 years for the treatment of alcohol hangover, alcoholism, muscle pain and measles. Many of its chemical components are found in commonly eaten foods.
Nutmeg. This is a commonly used spice but with high doses toxicity can be produced. The toxicity is caused by a chemical in the seeds, myristicin, which has anticholinergic properties. There is a single case report of a woman at 30 weeks gestation who used an excessive amount when making cookies. When she ate a cookie, she experienced sinus tachycardia, hypertension, and a sensation of impending doom. The fetus also had tachycardia and atropine-like poisoning was diagnosed. After 12 hours, both the mother and fetus made an uneventful recovery.
Peppermint. This popular flavoring appears to be harmless for the mother and developing baby when used in low doses. Peppermint oil is available in numerous topical and oral formulations. High doses can cause toxicity including death. High doses may also have abortifacient properties.
Pumpkin seed. When used as a food, this appears to be harmless for mother, embryo, and fetus. High doses such as those used in traditional medicine should be avoided because of the potential for toxic effects from the many chemicals that the seeds contain.
Raspberry leaf. Teas made from raspberry leaf are commonly used by pregnant women. There is one double-blind randomized placebo-controlled study that has evaluated the effect of raspberry leaf tablets on pregnancy outcomes. Compared to control, there were no differences for length of labor, mode of delivery or adverse effects on the newborn.
Safflower. The oil of safflower is commonly used in cooking and has also been given in traditional medicine as a laxative. It is doubtful that there would be any adverse effects on a pregnancy.
St. John's Wort. No toxicity in pregnant humans has been reported. Its use has been widespread and dates back several 1000 years. It is unlikely that it has any major teratogenic or developmental toxicity effects on pregnancy. It has been used for management of anxiety, depression, insomnia, inflammation and gastritis. In Germany, it is the most popular prescription drug of any type for treating mild depression. In the United States it is an over-the-counter supplement. It has fewer adverse effects than conventional prescription antidepressants but does not work as well as most prescription antidepressants.
Summary and Conclusions
There are many thousands of herbal products that patients might use for their purported health benefits. It is always important to ask patients not just what medications they are taking but also what supplements and herbal products they might also be using. Very few of these products have had any significant testing regarding safety and efficacy. This is especially true for any potential effects on fertility and pregnancy.
With few exceptions, a woman who takes an herbal product while trying to become pregnant or during pregnancy needs to be informed that the risk to her developing baby is unknown. As a precaution, frequent or high doses of herbal products even those deemed to be safe should generally be avoided.
