Herbs During Pregnancy and Lactation

Summary

Herbs During Pregnancy and Lactation

introduction:
Pregnancy is not a pathological condition, and therefore does not require medication, so the issue of drug-nutrient and drug-herb interactions in pregnancy does not strictly arise here. However, in the literature there are copious lists of herbs that are supposedly contraindicated in pregnancy, thus the following is included as general guidance for Interactions™ users.

The lists of herbs contraindicated in pregnancy are rarely in agreement, do not cite sources or references, and are often based upon speculative extrapolations from single isolated chemical constituents or animal studies. In addition, they have not been compiled by midwives experienced with herbs or by qualified herbal practitioners. Some qualified practitioners have fallen prey to the same tendencies. In the handful of cases where human studies do exist, interpretation may be problematic. For example, Zingiber officinalis (ginger) has been shown to be an effective treatment for the nausea of pregnancy, yet the German Commission E without explanation lists ginger as contraindicated in pregnancy.

Ultimately, the stance of the practitioner, which depends upon their clinical skills, knowledge and experience, is essentially what determines the use of herbs during normal pregnancy, labor, and lactation, as well as for complications of pregnancy. A recent survey showed that over 50% responding Certified Midwives (CMN's) used herbs for cervical ripening, induction and augmentation of labor and that the use of herbs is included formally in many, and informally in almost all certified midwifery education programs in the USA.
(Blumenthal M, et al. 1998; Brinker F.1998; McFarlin BL, et al. J Nurse Midwifery 1999;44(3):205-216; Newall C, et al. 1996.)

pregnancy: general concerns:
It is not the purpose of Interactions™ to produce another list of herbs contraindicated in pregnancy. However, the following general points should be noted:

• The use of medicinal herbs during normal pregnancy is best avoided altogether, particularly during the first trimester. Qualified practitioner guidance should be sought before using any herbs at any time during pregnancy.

• Certain herbs do have a long-standing reputation as partus preparator agents, for example Rubus idaeus (Red raspberry) and Mitchella repens (Squaw Vine); these are commonly used during normal second and third trimester pregnancy. Food herbs (Garlic, Ginger, Artichoke, etc.) are also generally recognized as safe during pregnancy.

• Normal complications of pregnancy can be treated effectively with herbal medicines. Herbal prescriptions for treatment of these complications should only be undertaken with the supervision of qualified herbalists experienced in the use of the agents and conditions involved. For a review of these issues and appropriate herbal treatments see for example: McQuade-Crawford A. 1997; Yarnell E. 1997.

• Plants containing overtly toxic (usually alkaloidal) constituents such as Aconitum napellus (Monkshood), Sanguinaria canadensis (Bloodroot), Bryonia alba (White bryony), etc. should be avoided during pregnancy and lactation.

• Fetoxicity and teratogenicity has been established for a few herbs, including Podophyllum peltatum and Scutellaria baicalensis. Other herbs, such as Eleutherococcus senticosus (Siberian ginseng) are known to protect against teratogenicity. Herbalist Kerry Bone points out that distinction should be made between known teratogens in known teratogenic plants, such as alkaloids from Lupinus, Veratrum, Conium and Solanum species; known teratogenic plants with unknown teratogens, such as Astragalus, Ferula and Nicotinia; and suspected teratogenic plants, such as Datura and Senecio species. Experienced midwives and herbal practitioners may use certain potentially toxic herbs such as Lobelia and Gelsemium, as adjuvants during labor and delivery, for stalled labor, dilation of the os and initiation and promotion of uterine contraction.

• Anthraquinone laxative herbs, such as Rhamnus purshiana (Cascara) and Rheum palmatum (Rhubarb Root) are commonly reported as contraindicated due to their "sacral irritant" effects, but evidence is lacking. Cassia senna (Senna) has been shown to be safe in pregnancy and lactation.

• Herbal "emmenagogues" (an older term originally describing a botanical agent that induced absent menses, including that due to pregnancy) should also be avoided in pregnancy, notably Caulophyllum thalictroides (Blue Cohosh). Experienced practitioners have used the same herb to treat threatened miscarriage, and as a third trimester partus preparator; once again demonstrating that the clinical skills and abilities of the practitioner are central in determining the relative safety and uses of herbs during pregnancy.

• Pure (volatile) essential oils of any kind should not be used internally during pregnancy due to their high degree of concentration and potential toxicity to mother and child. Abortifacient actions attributed to volatile oils, such as Mentha pulegium (Pennyroyal) are considered to be due to overwhelming maternal hepatoxicity rather than a direct uterine stimulation action.

• Several herbs are lactagogues (milk increasing) - a clinically proven example being Allium sativum (Garlic). Others are antilactagogues (milk decreasing); for example, Salvia officinalis (Sage) is traditionally regarded as antilactogogic, although clinical studies are lacking. Some herbal constituents such a berberine, present in Hydrastis canadensis (Goldenseal) and Mahonia spp. (Oregon Grape), are known to cross the blood-milk barrier. Since berberine displaces bound bilirubin, high doses of these herbs have been considered to increase the risk of neonatal kernicterus.

• Due perhaps to the legacy of the DES (diethylstilbestrol) catastrophe in the 1970's some physicians have warned against the consumption of phytoestrogen containing plants during pregnancy. Since phytoestrogenic constituents are only weakly estrogenic, it is unlikely that they will have any of the effects of powerful synthetic estrogen analogs. Nor is their epidemiological evidence, e.g., from high soy consuming populations that suggests phytoestrogens are problematic during pregnancy. However, in the absence of clinical evidence, prudence would suggest the avoidance of plant estrogenics during pregnancy: this reservation applies to therapeutic administration rather more than normal dietary consumption of phytoestrogenic foods.
(Bone K. Modern Phytotherapist 1999;4.3:10-13; McQuade-Crawford A, 1997; Yarnell E. Alt Comp Ther. April 1997, 93-100.)

For Phytoestrogens, see Herb Group: Ob/Gyn: Gynecological Herbs.




Herbs

For herbs used and/or contraindicated in pregnancy and lactation, see Summary Discussion above and consult references, especially Bone K. 1999; McQuade-Crawford A. 1997; Yarnell E. 1997.

Please read the disclaimer concerning the intent and limitations of the information provided here.
Do not rely solely on the information in this article.

References

Blumenthal M, et al. (eds.) The Complete German Commission E Monographs, Texas: American Botanical Council, 1998.

Bone K. Safe Use of herbs in Pregnancy. Modern Phytotherapist 1999; 4.3:10-13.

Brinker F. Herb Contraindication and Drug Interactions. Second edition. Sandy, OR: Eclectic Medical Publications, 1998.

McGuffin M, et al. (eds.) AHPA Botanical Safety Handbook. CRC Press, 1997.

McFarlin BL, et al. A national survey of herbal preparation use by nurse-midwives for labor stimulation. Review of the literature and recommendations for practice. J Nurse Midwifery 1999; May-Jun;44(3):205-216

McQuade-Crawford A. Herbal Remedies for Women. Rocklin, CA: Prima Publishing, 1997.

Newall C, Anderson L, Phillipson JD. Herbal medicines: A Guide for Health-Care Professionals. London. Pharmaceutical Press, 1996.

Trickey R. Women, Hormones and the Menstrual Cycle. Sydney, Australia: Allen and Unwin, 1998 .

Yarnell E. Botanical medicine in Pregnancy and Lactation. Alternative and Complementary Therapies 1997, April ; 93-100.