
Since we are on the topic of reproductive health, I thought this was an appropriate time to bring this up, but first I must tell readers who are new to this site a story. I grew up on a small farmstead in Iowa near a very tiny town where my great-grandmother had sometimes helped other families out as a midwife. She taught my grandpa’s sister Gladys to take over when she was too old. There’s a delightful story that still gets told about how Gladys kept some local twins alive by putting them in cereal boxes in a warm oven.
My mother used a respectable number of home remedies while raising her children, even though she didn’t follow that path. So, I first learned about domestic medicine from my family and neighbors. That’s just how life was in a lot of poor rural areas. No one put on airs, and we all helped one another out.
I was in my mid-twenties and had a toddler and an infant before I met a person who called themselves “an herbalist” and that was quite the experience. I was not used to herbal remedies being marketed to me. That’s what we all did because we couldn’t afford a doctor.
I went on to learn that there were a number of these folks who commodified herbalism in the mid-to-late twentieth century. They had started charging for “consultations” and selling products. Interventions containing difficult to obtain ingredients were branded as being “traditional” over more easily acquired historical counterparts. This is what people mean when they say that capitalism is responsible for the erasure of traditional knowledge.
While I was writing my last several posts, I was reminded once more by how different the historical materia medica is from modern thinking, especially when it comes to midwifery. There are plants that have all but disappeared from use and those that popped up in the modern materia medica that were used quite differently at one point.
Red raspberry leaf is one that is frequently mentioned in modern materia medica as an herb that has a long history of use by midwives. I decided to investigate because that didn’t track with what I knew of it.
Knowing full well that just because it was not done in my region doesn’t mean that it wasn’t done at all, I started combing through the various research databases I use. It’s worth pointing out that there are over sixty thousand texts in the Early English Books Online database and another ten thousand in the databases where I transcribe handwritten documents.
I found about sixty references to raspberries in EEBO most of which were making raspberry wine or jam. John Pechey (ca 1700) wrote about including a syrup made from berries in a cordial before delivery.
I found a couple instances of wild raspberry leaves being used to alleviate rheumatism and sciatica in the Schools’ collection (ca 1930s). Sciatica often develops in the third trimester of pregnancy. So maybe that’s how it got started?
I also discovered that I wasn’t the first to tackle this as Graeme Tobyn mentions in his history of the plant medicine of the learned elite that there appears to be no use of Rubus idaeus before the Renaissance, except for some authors mentioning it as a substitute for blackberry leaves used for postpartum hemorrhage because it had a similar astringency.[i]
From what I have been able to gather, Thomsonian medicine popularized raspberry leaf tea. Thomson takes credit for “discovering” it in New Guide to Health,[ii] although he certainly didn’t limit the scope of his recommendations to reproductive care. Thomson primarily recommended the tea for canker which he believed to be a coating that lined the stomach and intestines when one was ill. He taught that eventually canker became so thick that it prevented the absorption of food.
He did suggest a strong red raspberry leaf tea as a delivery mechanism for large amounts of cayenne during labor and then said to give it to the newborn with a little milk and sugar to prevent a sore mouth. I am not sure why Thomson thought infants had sore mouths?
Mormon physicians were especially fond of the drink- most likely since they were told to avoid stimulants like caffeine and tea. In Keith Terry’s thesis that catalogued the materia medica of the women doctors who helped settle Utah, raspberry leaf is listed for the use of canker, fever and dysentery.[iii] Another time I will write about Mormon elders sending young Mormon women to the Women’s Medical College in Philadelphia to be educated as doctors in the late 1800s.
Thomson’s “discovery” had an international impact. Physiomedical physicians on both sides of the pond began recommending red raspberry leaf tea. Dr. Sarah Webb’s Diseases of Women and Children[iv]recommended raspberry leaf tea as part of dietary plan for pregnancy. Webb suggested the tea as a substitute for coffee or tea writing “the value of Raspberry leaves is that they are a mild astringent, and cleanse tissue of any morbific material adhering to them, thus allowing them to relax and contract in a natural manner.” Later she suggests it interchangeably with blackberry leaves for children with diarrhea and cholera.
Webb said the benefits were “better health, less stomach trouble and less swelling of the feet and limbs.” Like Thomson, she seems to believe this astringency has some sort of benefit on digestion and assimilation which isn’t entirely off base given tannins actions on gastrointestinal epithelial tissue. But lest we take Dr. Webb’s dietary advice too seriously, she also thought that restricting the mother’s diet could keep a fetus’ bones from hardening to make labor easier on the mother.
Recommendations like this seemed to catch the eye of the conventional medical community. In a British Medical Journal published in 1941 two physicians suggested fragarine[v] as the name for an active principle in red raspberry leaf that they had yet to isolate. [vi] They simply theorized as to its existence and a medical myth was born.
What makes this more confusing is that an 1878 journal article had already assigned this name to a tannin found in strawberry roots[vii], but it does not appear that the authors of the 1941 article are aware of the previous use of that name. An anthocyanidin glycoside named fragarin has been identified in strawberry leaves which do hold a place in the early modern materia medica. I will leave that to another post, though.
Regardless, as you can see in the attached document, no such constituent has been identified in red raspberry leaves. Errors like this can generally be attributed to people who only read the abstracts of journal articles, or even worse only the titles.
What red raspberry leaves have is a substantial amount of potassium, magnesium, calcium, and other minerals that are vital to proper smooth muscle signalling. This could very well account for the effect the aqueous extract has on uterine smooth muscle. I would like to see studies on how it impacts smooth muscle tissue from other areas of the body. I conjecture that it would be similar. I use the leaves as a caffeine-free base for many of my nervine infusions.

You also don’t want to overlook the tannins and pectin in the leaves. Pectin is known to increase daily diuresis which means increasing the amount of sodium and chlorine filtered from the urine in the kidneys which in turn draws excess water from the body usually resulting in increased urine output. While I can’t find a study done on the leaves, the pectins in the berries at least seem to be potassium sparing. [viii]Tannins are known to slow intestinal peristalsis and increase the absorption of water in the small intestine and colon by reducing intestinal permeability. [ix]
It seems that, unlike some other natural diuretics, red raspberry leaves kind of balance out and more importantly don’t contain any oxalic acid, although this is true of most berry plants. You could just as easily substitute black raspberry or blackberry leaves.
The last thing I need is people getting all worked up saying I said not to drink the tea, because that is not what I am saying. I agree with Webb that a beverage tea blend made with a base of red raspberry would certainly be far more nutritious than a cup of coffee. Being well nourished going into labor is a good call no matter how you choose to accomplish that. I just want people to stop saying that it has an affinity for the uterus because that is physiologically unsound.
I see only two concerns with frequent use in pregnancy.
- Ingesting pectins and tannins at the same time as supplements can interfere significantly with the absorption of nutrients. I recommend taking meals and prenatal supplements with water.
- Keep in mind the impact that diuretics can have on the concentration of oxytocin in the bloodstream. Red raspberry leaf might be too much diuretic for some pregnant people. If a person complains of a lot of Braxton Hicks contractions, I tell them to back off the tea. I don’t think you will run into this problem unless you are combining the leaves with other astringent diuretics like nettle and dandelion leaf.
[i] Tobyn, Graeme, Alison Denham, and Margaret Whitelegg. The Western Herbal Tradition: 2000 Years of Medicinal Plant Knowledge. Edinburgh: Elsevier, 2011.
[ii] Thomson, Samuel. New Guide to Health, or, Botanic Family Physician [Microform] : Containing a Complete System of Practice upon a Plan Entirely New, with Description of the Vegetables Made Use of, and Directions for Preparing and Administering Them to Cure Disease : To Which Is Prefixed a Narrative of the Life and Medical Discoveries of the Author. 2nd ed. Brockville, Ontario: Printed for W. Willes, by W. Buell Jr., 1831. http://archive.org/details/cihm_01684.
[iii] Terry, Keith Calvin. ‘The Contribution of Medical Women During the First Fifty Years in Utah’. MA, Brigham Young University, 1964. http://scholarsarchive.byu.edu/etd/5167/.
[iv] Webb, Sarah A. Diseases of Women and Children. Worcester, England: National Association of Medical Herbalists, 1930.
[v] Not to be confused with fragarin which is an anthocyanidin glycoside. PubChem. ‘Pelargonidin 3-Galactoside’. Accessed 11 August 2022. https://pubchem.ncbi.nlm.nih.gov/compound/16218556.
[vi] Whitehouse, Beckwith. ‘Fragarine: An Inhibitor of Uterine Action’. British Medical Journal 2, no. 4210 (13 September 1941): 370–71.
[vii] Phipson, T.L. ‘On Some Substances Obtained from the Root of the Strawberry’. In The Chemical News and Journal of Industrial Science, 1878. 135.
[viii] Zhang, Y., Z. Zhang, Y. Yang, X. Zu, D. I. Guan, and Y. Guan. ‘Diuretic Activity of Rubus Idaeus L (Rosaceae) in Rats’. Tropical Journal of Pharmaceutical Research 10, no. 3 (2011). https://doi.org/10.4314/tjpr.v10i3.15.