CHAPTER 11 Pregnancy and Botanical Medicine Use and Safety
—Obstetrician in Friends, The One Where Rachel Is Late
The charge that herbal medications are not well tested in pregnancy is true, but it is just as true that conventional medications are not well tested in pregnancy. The medication-related embryopathies with which we are familiar are nearly all associated with conventional prescription drugs: thalidomide, anticonvulsants, ACE inhibitors, misoprostol, lithium, and isotretinoin. The most common embryopathy affecting humans is fetal alcohol syndrome, which is not associated with an herbal medication. This observation does not mean that herbal medications are safe, but only underscores the need to be well informed when prescribing in pregnancy. Let’s recommend medications in pregnancy that have been adequately studied, without assuming that all conventional medications are on one side of a divide and all herbal medications are on the other side.1
PREVALENCE OF HERB USE DURING PREGNANCY
Herbs have been applied in the treatment of difficulties arising during pregnancy and childbirth since time immemorial, with texts and treatises on the uses of herbs for childbearing problems dating at least back to ancient Egypt. Childbearing women commonly experience minor complaints for which the use of natural remedies may be preferable to the woman who perceives them as gentler and safer than OTC and prescription pharmaceuticals. The appropriate use of herbs medicinally during pregnancy requires specialized knowledge and a healthy dose of caution. This chapter presents a discussion of the prevalence of herb use during pregnancy and childbearing, possible risks, and general guidelines for responsible use. Subsequent chapters discuss the use of herbs for specific pregnancy concerns.
Herbal medicines are commonly used by pregnant women for a variety of complaints, as well as for nutritive and tonic purposes, such as the use of ginger to treat nausea and vomiting of pregnancy or the traditional use of raspberry leaf as a uterine tonic. There is considerable evidence of increasing herb prescribing by obstetric health professionals, particularly certified nurse-midwives (CNMs).2 The introductory quote to this chapter suggests a mainstreaming of herb use even by obstetricians—enough so that it would be mentioned by an OB-GYN on the popular television sitcom Friends when one of the characters is seeking advice for her postdates pregnancy.
Epidemiologic studies and surveys from the United States, United Kingdom, and Australia estimate a range of approximately 7% to 45% of women using herbs during pregnancy. 2 3 4 5 A recent survey of 587 pregnant women by Glover et al. revealed that a total of 45.2% of participants in a rural obstetric population had used herbal medications (95.8% had used prescription and 92.6% had self-prescribed OTCs).6 In another study, a one-page questionnaire examining the use of all prescription and nonprescription medications, including herbal remedies, was sent to parturients expected to deliver within 20 weeks who had preregistered with the hospital’s admissions office. Sixty-one percent of the women responded to the survey, with 7.1% reporting the use of herbal remedies. Only 14.6% of users considered herbs to be medications. Herbal medicine use was most prevalent (17.1%) in parturients in the 41- to 50-year age range (5.6% of parturients). In another study, approximately one-third of 463 postpartum women surveyed in the United States reported having used CAM therapies during pregnancy.7 Of 734 pregnant women that responded to one survey, 46% used herbal remedies at the recommendation of their health care provider; 54% did so at the recommendation of a friend of family member.2
Botanical medicine use is likely even higher in communities observing traditional practices, for example, among Hispanic Americans or Asian Americans, where herb use is an inherent cultural practice. Internationally, traditional herb use during pregnancy is common. For example, a report from the King Edward VIII Hospital in South Africa demonstrated use of a specific traditional herbal formula among 55% of 229 patients randomly selected for interview upon admission in early labor.8
Articles and studies published in prominent nurse-midwifery and obstetric journals (i.e., Journal of Nurse-Midwifery, Obstetrics and Gynecology, and Clinical Obstetrics and Gynecology) indicate that a large number of CNMs use herbal medicines clinically or are interested in learning to do so. 9 10 11 12 A study of CNMs in North Carolina indicated that 90% of midwives recommend CAM therapies to patients, with 80% of respondents suggesting herbal therapies for labor stimulation.9 A survey of 596 health care professionals in Leicestershire, United Kingdom, found that 34% of midwives and 18% of nurses used complementary therapies in their practices.13 According to Jeanne Raisler, Associate Editor of the Journal of Nurse Midwifery, “Herbal healing is probably the complementary therapy most widely used by midwives.”12
WHY ARE HERBS BEING USED DURING PREGNANCY?
One of the primary reasons women cite for stopping conventional medication during pregnancy is concern for risks to the fetus.2 A recent report by Lo and Friedman indicates that greater than 90% of all conventional medications prescribed for pregnant women have not been proved safe for use during pregnancy.14 The specter of the thalidomide and DES disasters are sufficiently recent to remind us of the hazards of “safe” pharmaceutical use during pregnancy. Many pregnant women turn botanical therapies to pharmaceutical medications believing them to be safer and gentler. Women planning natural birth also may feel that the use of herbs is more philosophically harmonious with their overall belief that childbearing is a natural experience and are more likely to use herbal preparations than those who are not preparing for natural birth.2 Thus, the use of herbal medicines represents both a philosophic and medical choice.
Midwives recommend herbal medicines for a variety of reasons, including support of patient choice, a shared belief in the naturalness of birth and the use of herbs as a natural extension of this belief, and as a way to help pregnant and postpartum women avoid more invasive and costly medical interventions that may be perceived as overly aggressive or unnecessary.15 For example, Tiran suggests that the possibility of cephalic version of breech presentation through the use of moxibustion (see Breech Presentation) may avoid the costs (and risks) of cesarean section and adequate management of nausea and vomiting of pregnancy (NVP) may reduce hospital admission for hyperemesis gravidarum.16
Midwives are in a key position to interface with pregnant clients about the use of botanical therapies. The philosophic compatibility between herbal medicine, midwifery, and nursing care philosophies reinforces a perceived “rightness” of botanical medicine use.11,17,18 Unfortunately, few midwives are adequately trained in the use of botanical medicines during pregnancy. Education on the use—or at least safety and risks— of botanicals in the childbearing cycle should be a requisite part of training for all midwifery and obstetric care providers.
LACK OF TRAINING IN OBSTETRIC BOTANICAL MEDICINE USE
The medical and alternative literature on botanicals for pregnancy and birth often contains erroneous or inadequate information on the use of herbs during childbearing.15,19,20 Herbs may be recommended, for example, with insufficient explanation of possible risks, without specified dosage ranges, and may be based on theoretic or academic knowledge rather than training or clinical experience. In one well-cited survey conducted by McFarlin and O’Rear of nurse-midwives on their use of herbal remedies during pregnancy, most midwives who responded reported that they had learned about the use of herbs by word of mouth.21 Several articles report on the need for further training in botanicals for nurse-midwives, citing its absence from curricula.12,16,22
Lack of practitioner training in botanical medicines for pregnancy might mean that practitioners are inappropriately recommending botanical therapies to their patients, either by recommending herbs that might be contraindicated, recommending inappropriate doses, not identifying safe and high-quality botanical products for patients, or recommending inappropriate durations of use. Further, practitioners with limited knowledge cannot accurately evaluate advice patients might receive from other sources, such as the Internet, a common source of misleading information on herbs and pregnancy.23 There is clearly a need to include education on obstetric botanical medicine use in the growing number of CAM education programs in medical and nursing programs. Adequate practitioner knowledge is critical to the well-being of both patients involved in the prenatal and lactation dyad.
HERBS MOST COMMONLY USED DURING PREGNANCY
The herbs cited in the medical literature as those most frequently used for pregnancy complaints varies slightly among studies, but includes echinacea, St. John’s wort, ephedra, peppermint, spearmint, ginger root, raspberry leaf, fennel, wild yam, meadowsweet, blue cohosh, black cohosh, red raspberry leaf, castor oil, evening primrose, garlic, aloe, chamomile, peppermint, ginger, echinacea, pumpkin seeds, and ginseng. In one study, patients cited lower GI problems, anxiety, nausea and vomiting, and urinary tract problems as the most common reasons for using complementary therapies in pregnancy.2,4,7,10,23 Midwives most frequently recommend herbs for nausea and vomiting, labor stimulation, perineal discomfort, lactation disorders, postpartum depression, preterm labor, postpartum hemorrhage, labor analgesia, and malpresentation.9 Most of the herbs cited as commonly used are generally considered safe and gentle, even for use during pregnancy; however, several including blue cohosh, ephedra, aloe (internally), and St. John’s wort (internally) are not appropriate and may even be harmful (see further discussions on blue cohosh throughout in this and subsequent sections of this chapter).
SAFETY, EVIDENCE, AND POTENTIAL ADVERSE EFFECTS OF BOTANICAL USE DURING PREGNANCY
Little is known scientifically about the risk of using herbs during pregnancy, as most have not been formally evaluated and ethical considerations severely limit human clinical investigation during pregnancy.2,5,9,24,25 Much the same can be said for the use of many pharmaceuticals during pregnancy. Bone identifies five primary risks associated with the use of herbs during pregnancy:26
An additional potential risk is the consequences of delayed administration of necessary medical therapy in favor of herbs, regardless of their safety.27 Most of what is currently known about botanical use during pregnancy is based on a significant body of historical, empirical, and observational evidence, and limited pharmacologic and animal studies. There has been little evidence of harm from the use of botanicals during pregnancy. When apparent adverse events have occurred, cause and effect have been difficult to establish because of a wide range of confounding factors.23 Also, adverse events reports typically have involved the consumption of known toxic herbs, adulterations, or inappropriate use or dosage of botanical therapies. In general, there have also been relatively few case reports of adverse drug interactions involving herbal medicines.28 Overall, most herbs have a high safety profile. Many practitioners take this as proof of safety, believing that whole herbs are inherently safer than concentrated pharmaceutical drugs.10,11 However, lack of proof of harm is not synonymous with proof of safety. Some of the harmful effects of herbs may not be readily apparent until long after use has been discontinued, or may only occur with cumulative use.
There is a paucity of human clinical trials on the safety and efficacy of Western botanical therapies during pregnancy. Two human clinical trials evaluated raspberry leaf for its effects on labor outcome with positive findings, a study conducted on echinacea safety after varying lengths of pregnancy use found no harmful effects, and several studies have evaluated the safety and efficacy of ginger root for the reduction of NVP, finding it safe and effective. 29 30 31 Most often, the results of clinical trials are positive.3 Nonetheless, many researchers feel that in the absence of proof of safety, herbs should be entirely avoided during pregnancy.3 However, many midwives and pregnant women continue to use herbs based on satisfaction with their safety, efficacy, and outcomes, and on the knowledge that many pharmaceutical preparations recommended during pregnancy also carry unknown risks.
Controls over the manufacturing of herbs do not entirely protect consumers from the accidental or deliberate adulteration, sophistication, or contamination of herbal products, all of which can pose problems during pregnancy. In one study of 200 different herbal products, 83% were found to be contaminated with undeclared pharmaceuticals or heavy metals, including lead, arsenic, and mercury.5 Adulteration occurs when one herb is accidentally or deliberately substituted for another. Rarely, toxic herbs have been found as adulterants in otherwise completely benign herbal products, for example, adulteration of skullcap (Scutellaria lateriflora) with the toxic Teucrium, or Digitalis spp. (foxglove) with common plantain (Plantago spp.). One case in the literature reports on the substitution of the herb Periploca sepium for Eleutherococcus senticosus.26,32 This substitution resulted in a case of hyperandrogenization of the fetus (“hairy baby syndrome”) as a result of the mother mistakenly taking the adulterated product throughout her pregnancy. Chinese patent products and imported Asian herbal formulae should be viewed with utmost caution during pregnancy, as they are well known to contain adulterants, heavy metals, and added pharmaceutical medications frequently not listed on the label, all of which can pose a threat to the safety of the pregnant woman and her fetus.
Negative outcomes have been reported for a limited number of herbal products used by parturient women. Ernst provides a through review of these in Herbal Medicinal Products during Pregnancy: Are They Safe?3 Causality remains uncertain. Adverse reports cited by Ernst and others include:8,10,33
Other herbal products that have been associated with increased complications include a possible correlation between a German sinus preparation (Sinupret) and increased rates of miscarriage, stillbirth, and malformations; increased rate of meconium-stained amniotic fluid with maternal use of castor oil; and increased meconium staining and possibly related fetal distress with use of a traditional South African herbal pregnancy formula called isihlambezo, and a case of a baby born with veno-occlusive disease after the mother consumed a coltsfoot-containing cough syrup throughout her pregnancy.3,8
