• Echinacea. This herb is used topically to enhance wound healing and systemically as an immunostimulant. An IV formulation is used in Germany but is not available in the United States. It also has been recommended to assist in the prevention or treatment of viral upper respiratory tract infections. Its use in pregnancy is limited to one small study.
• Evening primrose oil. The oil contains two essential fatty acids: cis-linoleic and gamma-linolenic acid. In a national survey of nurse-midwives, it was the most frequently used herbal preparation for the induction of labor. No adverse effects have been reported in the fetus or newborn from this use. The doses used varied widely and included both oral and vaginal routes of administration. In addition, the oil has been used for rheumatoid arthritis and diabetic neuropathy, but there are no reports of these uses in pregnancy.
• Garlic. Garlic has been used for food flavoring since ancient times and appears to be safe during pregnancy. Some components cross the placenta, as shown by garlic odor in the amniotic fluid and on the newborn’s breath. Very high doses have the potential to induce menstruation or uterine contractions, but apparently these effects have not been reported.
• Ginger. No reports of ginger-induced developmental toxicity have been located. Ginger has been used as antiemetic for nausea and vomiting of pregnancy.
©leungchopan/thinkstock.comGinseng root
• Ginseng. The root is the most important part of this plant that is found throughout the world and has been used in medicine for more than 2,000 years. The herb has been promoted for multiple pharmacologic effects, including adaptogenic, CNS, cardiovascular, endocrine, ergogenic, antineoplastic, and immunomodulatory effects.
Hypertension and hypoglycemia have been reported in nonpregnant patients, but not in the limited human pregnancy data. A brief 1991 study compared 88 women who took the herb during pregnancy with 88 controls. No differences between the groups were found with regard to the mode of delivery, birth weight, low birth weight (< 2,500 ), preterm delivery (< 37 weeks), low Apgar score (< 7), stillbirths, neonatal deaths, or maternal complications (Asia Oceania J. Obstet. Gynaecol. 1991;17:379-80).
• Ginkgo biloba. The limited animal reproduction data suggest low risk, but there is no reported human pregnancy experience. Nevertheless, it is an ancient herbal preparation that is commonly used for organic brain syndrome, circulatory disorders, asthma, vertigo, and tinnitus. Because of its widespread use, it is doubtful that a major teratogenic effect would have escaped notice, but more subtle or low-incidence toxic effects may not have been detected.
• Kudzu. No human or animal data regarding pregnancy have been located. The herb has been used for more than 2,500 years for the treatment of alcohol hangover, drunkenness, alcoholism, muscle pain, and measles. Many of its chemical constituents can be found in foods. Nevertheless, high, frequent doses should be avoided.
• Nutmeg. This is a commonly used spice but, as with any herb, high doses can produce toxicity. The toxicity is caused by a chemical in the seeds, myristicin, which has anticholinergic properties. A woman at 30 weeks’ gestation misread a recipe and used a whole grated nutmeg rather than 1/8 teaspoon when making cookies. When she ate a cookie, she experienced sinus tachycardia, hypertension, and a sensation of impending doom. The fetus had tachycardia, and atropine-like poisoning was diagnosed. After about 12 hours, both mother and fetus made an uneventful recovery and a healthy infant was born at term.
©matka_Wariatka/thinkstock.comPeppermint oil
• Passion flower. The name of this herb may refer 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. As with many herbs, it contains a large number of chemicals, none of which have undergone reproductive testing. No reports describing the use of this herb in human pregnancy have been located. However, because it has uterine stimulant properties, the oral formulation is best avoided in pregnancy.
• Peppermint. This popular flavoring appears to be harmless for the mother and developing baby when low, recommended doses are ingested. Peppermint oil is available in numerous topical and oral formulations. High oral doses, however, can cause significant toxicity, including death. During pregnancy, ingestion of more than the recommended doses is unsafe because of possible emmenagogic and abortifacient properties.
• Pumpkin seed. This herb, when used as a food, appears to be harmless for the mother and embryo-fetus, but no reports describing its use in pregnancy have been located. High doses, such as those used in traditional medicine or in eating disorders, should be avoided because of the potential for toxic effects from the many chemicals these seeds contain.