Herbs in Pregnancy: Are They Safe?
Herbs have been used for the treatment of discomforts and common problems arising during pregnancy and childbirth dating at least back to ancient Egypt.
Little is known scientifically about the safety of most herbs during pregnancy, as most have not been formally evaluated and ethical considerations limit human clinical investigation during pregnancy. However, much the same can be said for the use of many pharmaceuticals during pregnancy, most of which have not been tested or proven safe in pregnancy. Even medications previously thought to be safe in pregnancy, including Tylenol, have now been found to cause potential problems for baby. And as many as 90% of all pregnant women will be prescribed some medication during pregnancy!
Most of what is currently known about botanical use during pregnancy is based on a significant body of historical, empirical, and observational evidence, with some pharmacologic and animal studies. Overall, most herbs have a high safety profile with little evidence of harm. Pregnant mommas commonly experience minor symptoms and discomforts for which the use of natural remedies may be gentler and safer than over-the-counter (OTC) and prescription pharmaceuticals.
Few reported adverse events have occurred, and those that have typically involved the consumption of known toxic herbs, adulterations, or inappropriate use or dosage of botanical therapies. 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 after use has been discontinued, or may only occur with cumulative use, so it’s important to be smart and safe and use only those herbs in pregnancy with a proven track record and a good safety profile.
Schools of thought differ on whether herbs should be used during pregnancy. Some believe that since most herbs are not proven safe during pregnancy, they should be entirely avoided, while others see certain herbs more as foods that can provide an additional source of nutrition during pregnancy, or as tonics which can encourage and support optimal pregnancy health and uterine function.
Perhaps the most reasonable approach to herb safety is a “risk: benefit” one that takes into consideration the safety of the individual herb, the severity of the symptom or condition and comparing this to the safety of the corresponding conventional medical approach.
Certain signs and symptoms arising during pregnancy always warrant medical attention, and should not be treated with herbs. These include:
- Persistent vaginal bleeding
- Initial outbreak of herpes blisters during the first trimester
- Severe pelvic or abdominal pain
- Persistent, severe mid-back pain
- Edema of the hands and face
- Severe headaches, blurry vision, or epigastric pain
- Rupture of membranes prior to 37 weeks pregnancy
- Regular uterine contractions prior to 37 weeks pregnancy
- Cessation of fetal movement
Using Herbs During Pregnancy
The safest approach to the use of herbs during pregnancy is to avoid herbs during the first trimester unless medically indicated when there is not a more effective or safer medical option (i.e., nausea and vomiting of pregnancy-NVP, threatened miscarriage) and after this to use herbs that are known either scientifically or historically to be safe during pregnancy.
Beverage and nutritive teas that are known to be safe in moderate amounts (i.e., red raspberry, spearmint, chamomile, lemon balm, nettles, rose hips) can be considered reasonable for regular use in pregnancy. Using normal amounts of cooking spices is considered safe as well.
There are a number of herbs whose constituents (chemical composition) are mostly gentle, nutritious substances such as carbohydrates vitamins, and minerals and which can be used safely in pregnancy as basic daily tonics, for example, nettles (Urtica dioica), milky oats (Avena sativa), and red raspberry leaf (Rubus idaeus). Several herbs have also been scientifically proven to be safe during pregnancy. These are presented in the first chart, below.
An herbalist, midwife, or naturopathic or integrative physician trained in the use of botanicals during pregnancy should be consulted when using herbs medically – that is, to treat a specific symptom or medical condition beyond those described in this article.
In addition to common pregnancy symptoms, when we’re pregnant and nursing we also get the same run of the mill mild illnesses everyone else gets – colds, indigestion, headache, etc., for which herbs can be helpful and even safer than OTC meds. Many of these problems can be addressed safely and gently with mild herbs such as echinacea, ginger, or chamomile respectively.
The following chart provides an overview of a number of herbs that have been demonstrated to be safe for use during pregnancy through clinical trials or scientific evaluation of safety.
Herbs Considered Safe in Pregnancy
Herbs to Definitely Avoid
While a number of herbs are known to be safe in pregnancy, there are numerous herbs that should be avoided. Somewhere between these categories are herbs whose use is not appropriate for daily, routine intake, but which can be used if necessary for brief or more extended periods of time for specific conditions.
Licorice is an example of such an herb. Used short term for a sore throat, for example, for no greater than one week, it may be entirely safe and appropriate, however, it is contraindicated in patients with hypertension, and long-term use of even licorice candy containing actual licorice extract has been associated with preterm birth.
The herbs listed under each category are representative examples and are not exhaustive, but should definitely be avoided in pregnancy. Additional herbs may fall into any of these categories.
Topical applications, including vaginal use (i.e., for the treatment of vaginal infections), of most herbs is considered safe, however, some herbs, for example, poke root, pennyroyal oil, and thuja, which are known to be toxic, should be avoided internally and topically.
Note that when you see sorghum on the list of herbs to avoid – don’t freak out if you’re eating it – that’s fine – it’s concentrated use of certain species in huge amounts that’s the problem!
* Avoid internal use; external use may be acceptable under the guidance of an experienced botanical medicine practitioner. Note that sorghum in normal food use is considered safe.
Common Conditions During Pregnancy and Herbs for Treatment: An Overview
The herbs cited in the medical literature as most frequently used for pregnancy concerns 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, women reported lower GI problems, anxiety, nausea and vomiting, and urinary tract problems as the most common reasons for using complementary therapies in pregnancy. 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.
The Chart below, Herbal Treatment of Common Pregnancy Concerns, provides guidelines for commonly used botanical treatments for several pregnancy problems, and provides a brief discussion of the safety of the herbs presented.
Herbal Treatment of Common Pregnancy Concerns
[Note that an infusion is a strong tea, so if making with tea bags, use 2 per cup; an extract is the same as a tincture. The amount of alcohol in herbal tinctures is negligible and is considered safe in pregnancy within recommended typical use of the herbal product.]
Getting Ready for Birth: A Word about “Partus Preparators”
Partus preparators are herbs sometimes used during the last weeks of pregnancy to tone and prepare the uterus for labor. They have historically been used to facilitate a rapid and easy delivery. Herbs commonly used as partus preparators include blue cohosh (Caulophyllum thalictroides),black cohosh (Cimicifuga racemosa), partridge berry (Mitchella repens), and spikenard (Aralia racemosa), among others.
The use of such herbs to prepare women for labor begs the question of why one would use an herbal preparation to prepare the body for something it naturally knows how to do. Furthermore, the safety of these herbs prior to the onset of labor is questionable. Case reports have appeared in the literature suggesting an association between blue cohosh and profound ischemic episodes or myocardial infarction in the neonate.
Blue cohosh contains a number of potent alkaloids including methylcystine and anagyrine, the latter, which is known to have an effect on cardiac muscle activity. Other side effects of blue cohosh include maternal headache and nausea. Yet the use blue cohosh represents one of the one widely applied botanical medicines by midwives, including CNMs, and one of those most commonly included in late pregnancy formulas self-prescribed by pregnant mothers. Much of this is due to medical pressure for induction of labor by 40 weeks of pregnancy.
The risks associated with extended third trimester ingestion of blue cohosh specifically suggest that it should be avoided as a partus preparator.
Red raspberry leaf tea, 2 cups daily, on the other hand, is know to be safe in pregnancy, and several studies have now shown that taking it regularly in the last trimester can make labor easier, reduces the need for medical interventions in labor, and makes baby less likely to need any resuscitation. I’d say that this makes it a great herb to use for getting ready for birth!
Herbs can provide substantial relief for common symptoms and concerns that arise during pregnancy and childbirth. The power of herbs should be respected during pregnancy, and therefore, they should be used with caution. However, many herbs may be contraindicated on the basis of very limited findings, erroneous reports, or by association with a problem rather than a proven causal effect.
Many herbs that have not been evaluated may, nonetheless, offer simple, safe, gentle, and effective solutions for many common pregnancy problems ranging from anemia to vaginitis.
Good diet and nutrition, exercise, and healthful lifestyle including a positive outlook and strong social support are the cornerstones of an optimal childbearing experience.