Herbs in Pregnancy
By Sarah Day, CNM, IBCLC

Plants have been used for medicinal purposes since prehistoric times. Many prescription drugs used today are derived from plant sources or are the synthetic equivalent of the natural form of the chemicals in plants. Most of the companies which supply and sell health foods, vitamins and medicinal herbs base their commerce on their customer's belief that "natural" is best. Depending on the product and its use, that may or may not be true.

Willow bark and mexican yams are a great example of natural substances whose chemical components can have profound effects on the human body. However, not all natural products are useful to humans in the raw, natural state. Aspirin was originally extracted from willow bark, and the mexican yam contains compounds which can yield the hormone, progesterone. However, unlike willow bark, humans are unable to convert the sterols in yams into a humanly bioactive product; the yams must be processed to provide humanly useful steroids.

It is an exciting time in the field of medicinal herbs and natural remedies. Public interest in the topic is at the "irrational exuberance" level, as evidenced by the BILLIONS of dollars spent on these therapies. The public interest has spurred scientific interest on the claims of the proponents (and sales-people!) of the movement. Interest in herbs, natural remedies and alternative medicine is so great that the U.S. Congress has provided funds to the National Institutes of Health to create the National Center for Complementary and Alternative Medicine. The next century will bring a great deal of knowledge about the use of herbs and natural remedies in wellness and illness.

But, for now, dealing with herbal and natural therapies is a bit like buying a car off of a used car lot. Regarding the condition of the car, the salesperson is probably just repeating information that s/he was told, but has not tested to see if it is true. Unless you take the car to an honest, qualified mechanic who can inspect and test the car, you cannot be certain the car will perform as sold to you by the salesperson.

Much of the information about herbs and natural remedies is a lot like those used cars. The salespeople (including some of the health care practitioners prescribing them) are largely providing a product or service with a lot of heresay information.....which may or may not be true. Most of the information about herbs and natural therpies has never been adequately tested by that honest mechanic.

That does not mean that many herbs do not do much of what is claimed about them. Many herbs have powerful effects in the body.......both helpful and harmful. But the truth about them is difficult to determine since most herbs have not been adequately scrutinized by scientific study.

Medicinal herbs and natural remedies are not regulated by state or federal law.......thus, quality control, dosage, freshness, potency and other important factors may vary greatly between different manufacturers, or even different batches from the same manufacturers. In fact, the U.S. government's standards for food and food supplement labeling allow a company to use the word "natural" if the substance being described is in essence the same chemical as the one found in nature......even if the "natural" substance is synthesized in the factory. This is particularly true with "natural flavorings". Many of the chemicals which create tastes and smells in nature can now be synthesized from basic chemicals. For example, the natural "esters" found in strawberries which produce the strawberry's taste and smell can be made from non-strawberry-derived chemicals. If the esters produced synthetically are the same as those produced naturally, the manufacturer may label the flavoring as "natural"......even though that is far from most consumers' definition of "natural".

The creed is "buyer beware".  The effectiveness and quality of many natural products has not yet been scientifically studied. There has been a recent burst in the scientific study of herbs and natural remedies.......both from a standpoint of safety and effectiveness, and in hopes that new drugs may be discovered and marketed.

There is also a common perception that safety is a guarantee with all natural products.....and, that if a little is good, more must be better. A recent clinical case provides an extreme example of the potential problem with this perception.

Blue cohosh (Caullophyllum thalictroides) is a herb commonly "prescribed" in pregnancy. It is often confused with an entirely different plant called, black cohosh (Cimicifuga racemosa). Both are confusingly referred to by various sources as the Native American herb, squawroot. However, blue cohosh is probably the traditional squawroot (used as an abortafacient, a menstrual regulator, and in pregnancy to induce contractions of the uterine muscle).

In 1996, a woman in Washington state gave birth to a baby who immediately showed signs of cardiovascular and respiratory distress. The baby was transferred to a Neonatal Intensive Care Unit. Upon evaluation, it was shown that the baby had evidence of myocardial infarction (heart attack) and congestive heart failure (signs of heart/lung overload). Three different cardiologists performed six cardiac ultrasounds and concluded that the baby's problems were the result of the toxic effects of blue cohosh.

Blue cohosh contains 3 chemicals with known effects on the human body. Methylcytisine is a chemical similar to nicotine. Caulosaponin and caulophyllosaponin are smooth muscle stimulants. The uterus is composed of smooth muscle.....so is the heart. In non-toxic levels, blue cohosh probably does have some effect on the uterus' ability to contract.......and that is ultimately what happens in labor. However, in toxic level doses, the effects intended for the uterus may have a serious side effect on the heart and lungs.

The mother in this case was told to take a tablet (one per day) produced from blue cohosh, beginning at about 36 weeks gestation. She took three per day for 3 weeks. No other herbal remedies were used, and she did not use tobacco, alcohol or any street drugs during her pregnancy. Obviously, this is an extreme example. People also overdose on prescription medicines every day. However, many people assume that something which is natural must be effective and cannot be harmful.

Because of the lack of regulation of herbal therapies in the U.S., consistent quality, purity and dosage remain significant problems in the herbal remedy industry. When a pregnant woman uses any drug-like substance (legal or illegal, prescribed or over-the-counter, natural or synthetic) she must question the potential effects of the substance on herself and her baby. This is often difficult with substances which are unregulated, increasingly sold freely on the shelves of major stores, and advertised as being "safe".

The 1990's are seeing a refreshing interest in the study of natural remedies. In the next ten years, we will see the results of scientific studies on many of the herbal and natural remedies. Hopefully, manufacturers and suppliers of medicinal herbs will produce standardized quantities and qualities of uncontaminated remedies for safe use by the public. Currently, the only way to determine the quality and quantity of a herbal product is with expensive chemical assays......which are not required, and rarely performed voluntarily by the manufacturers and suppliers.

The U.S. is now second only to Germany in the use of herbal therapies (based on monetary figures). However, in Germany, the industry is more regulated and the use of herbal therapies is well-integrated into mainstream health care. In the 1980's, Germany established a scientific panel, Commission E, to review the use of some 1,400 herbal remedies. The findings of Commission E are currently considered to be the closest thing to a scientific standard on claims of effectiveness of herbal remedies. China has a long history of the use of herbal therapies which continues to the present. However, the purity and dosage of Chinese herbs is presently considered to be significantly suspect. There are multiple reports of contamination and misidentification of Chinese herbs.

What follows is a description of some of the more popular herbs used in pregnancy and childbirth. An attempt has been made to list and differentiate the "claims" of the substance from the "scientific evidence". If you take a herbal remedy for any reason, let your doctor or midwife know. Many of the herbs recommended for use late in pregnancy (to facilitate labor) are also recommended for use in early pregnancy as abortifacients (to cause abortion).

Black Cohosh
(Cimicifuga racemosa)

Claims: abortafacient; treatment of premenstrual and menstrual symptoms.
Scientific evidence: This is one of the components of an old remedy, Lydia Pinkham's Vegetable Compound. Black cohosh contains compounds which were believed to have a weakly estrogenic effect. There is some evidence which suggests some effect on reproductive hormone production (particularly luetinizing hormone), and some relief of both painful menstrual periods and menopausal symptoms. May lower low-density lipids in the blood. The most recent studies show that the any estrogen-like effects are negligible.
Use in Pregnancy: Commonly used by herbalists and some midwives in pregnancy in combination with blue cohosh and pennyroyal to induce or augment labor contractions, a practice that is difficult to support given the lack of quality control in the U.S. and the potential for serious harm.

Blue Cohosh
(Caullophyllum thalictroides)

Claims: abortafacient, uterine stimulant.
Scientific evidence: contains chemicals which do stimulate smooth muscle, but there are no studies on its safety in pregnancy. There is a case report of a womem who took 3 times the recommended daily dose for 3 weeks prior to delivery- the baby was born with congestive heart failure (Journal of Pediatrics; 132[3]).
Use in Pregnancy: This herb is used commonly by herbalists and midwives to "tone" the uterus and stimulate labor. It appears to be potentially dangerous if misused. Commonly used by herbalists and some midwives in combination with black cohosh and pennyroyal, a practice that is difficult to support given the lack of quality control in the U.S. and the potential for serious harm.

Cranberry
(Vaccinium species)

Claims: urinary tract antiseptic/antibiotic.
Scientific evidence: one study suggests that one of renal metabolites of cranberry juice inhibits E. coli bacterial adhesion to the bladder wall. One good study showed a reduction in urinary tract infection in older women.
Use in Pregnancy: Since urinary tract infection can be a serious complication of pregnancy, it is not recommended that women treat themselves for symptoms of infection. Cranberry juice may be used as a complementary treatment or as a preventive measure to avoid urinary tract infection.

Echinaecea
(Echinacea angustifolia, E. pallida, E. purpurea)

Claims: immune stimulant (especially against cold and flu).
Scientific evidence: There are compounds in all of the three varieties which have some immunostimulatory effects, at least in the laboratory (in vitro and animal studies). The German literature abounds with evidence that supports echinaecea's positive effects on the immune system (injectable preparations of the herb are available there). In the U.S., some recent, small clinical trials do not support the folk claims.
Use in Pregnancy: cannot be recommended (especially any injectable form), though it is probably widely used.

Ephedra
(Ephedra species; ma huang)

Folk claims: energizer.
Scientific evidence: the active ingredient, ephredine, is well known in Western medicine. It is a potent nasal decongestant, appetite suppressant and cardiovascular stimulant. There have been deaths related to overdose in its abuse as a stimulant and as a weight-reducing agent.
Use in Pregnancy: Ephedra and its metabolites should not be used in pregnancy except when prescribed and administered by a licensed medical provider.

Garlic
(Allium sativum)

Claims: antiseptic, antibiotic, antihypertensive, treatment of elevated blood lipids.
Scientific evidence: there is evidence which suggests that garlic may lower harmful blood lipid levels, and thus, may protect against stroke, heart disease and hypertension. More recent studies refute the positive effects of garlic on lowering blood lipids.
Use in Pregnancy: as a food condiment in dietary amounts.

Ginger
(Zingiber officinale)

Claims: antiemetic (to prevent nausea and vomiting).
Scientific evidence: there is some evidence that shows some benefit to the use of ginger as an antiemetic.
Use in Pregnancy: commonly used in foods and teas; probably safe, and possibly effective in the treatment of nausea.

Ginseng
(Panax ginseng [american], P. quinque [oriental], Eleutherococcus senticosus [siberian])

Claims: cure-all.
Scientific evidence: there is some evidence which supports the use of ginseng for fatigue and poor concentration. A particular problem with ginseng is the purity and quality between any two sources. One study tested advertised sources of ginseng, and found that 25% contained no ginseng at all.
Use in Pregnancy: use in pregnancy has not been studied; therefore, highly not recommended.

Ginkgo Biloba
(Ginkgo biloba)

Claims: enhanced memory; Alzheimer disease improvement; slows aging process; antidepressant; vascular disease improvement.
Scientific evidence: one of the chemicals in ginkgo is a potent blood-thinning agent and may have benefits in all of the folk claims listed.
Use in Pregnancy: use in pregnancy has not been studied; therefore, highly not recommmended.

Marijuana
(Cannabis sativa)

Claims: antiemetic (to prevent nausea and vomiting).
Scientific evidence: somewhat effective in the treatment of nausea associated with cancer chemotherapy.
Use in Pregnancy: studies have shown higher rates of lower birth weights and meconium passage prior to birth in mothers who use marijuana, also it is illegal to possess.

Moxa, Moxibustion
(with Artemsia vulgaris [mugwort])

Claims: treatment of nausea in pregnancy; treatment of breech presentation.
Scientific evidence: one study showed a significant reduction in the number of breech infants at term when moxabustion (at acupoint BL 67) was used in the 2 months prior to delivery.
Use in Pregnancy: may be effective as an alternative to external version in the correction of breech presentation.

Pennyroyal
(Mentha pulegium [one of the mints], and Hedeoma pulegioides)

Claims: abortafacient, uterine stimulant, improvement of menstrual flow, water purifier, headache treatment.
Scientific evidence: Contains the ketone, pulegone (which is also found in peppermint). There are valid scientific reports dating back to the late 19th century documenting DEATHS due to use of pennyroyal oil, which include liver failure, renal failure and blood clotting abnormalities.
Use in Pregnancy: has been used in conjunction with blue cohosh and black cohosh to induce or augment labor contractions, but is a potentially dangerous herb; therefore, highly not recommended.

Red Raspberry
(Rubus idaeus, R. strigosus)

Claims: uterine stimulant.
Scientific evidence: Contains tannins (which act as astringents) and the alkaloid, fragine. In test-tube experiments, contractions of pregnant human uterine muscle were produced when stimulated by red raspberry extracts.
Use in Pregnancy: this plant yields the common raspberry is undoubtably quite safe and nutritious. Commonly used by herbalists and lay midwives, it should not be used after confirmation of pregnancy until about the 7th month as it can cause preterm uterine contractions.

St. John's Wort
(Hypericum perforatum)

Claims: antidepressant, anti-inflammatory, diuretic.
Scientific evidence: some evidence has shown better-than-placebo benefit in treatment of mild depression. Studies have shown that an antidepressant effect may be due to the same actions common in more medically acceptable antidepressant agents, i.e., MAO inhibition and serotonin reuptake inhibition.
Use in Pregnancy: use in pregnancy has not been studied; therefore, highly not recommended.

Vitamin B6
(pyridoxine)

Claims: relief of nausea and vomiting in pregnancy.
Scientific evidence: there is some evidence that shows B6 to have some benefit in the treatment of nausea and vomiting, and other evidence which refutes it.
Use in Pregnancy: The RDA for pregnancy is less than 1 mg/day (0.6). In daily doses of 10-25 mg, B6 is safe and possibly somewhat effective in relieving nausea and vomiting in pregnancy. Not recommended in dosages above 75 mg/day because of its known association with reversible neurological symptoms.

Vitamin E Oil

Claims: prevention of stretch marks.
Scientific evidence: none.
Use in Pregnancy: probably safe when used in vegetable oil form as a skin conditioner.

Witch Hazel
(Hamamelis virginiana)

Claims: treatment of hemorrhoids, vaginitis, poor uterine tone.
Scientific evidence: Well-known as an effective external astringent and anti- inflammatory agent. FDA-approved as an astringent.
Use in Pregnancy: Witch Hazel water (the aqueous steam distillate) applied as soaks to hemorrhoids temporarily relieves pain, burning and itching.

About the Author:

Sarah Day is a certified nurse midwife, mother of 2 children. She is on the All About Moms Ask A Midwife expert panel.

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Copyright © 2001 Sarah Day, All Rights Reserved Reprinted with Permission