# Round birthwort (Aristolochia rotunda)

**Aristolochia rotonda**

**Known today as.** *Aristolochia rotunda*.

Kind: Plant  
Poisoning: Aristolochic acid nephropathy (https://thethinkingpress.org/materia-medica/poisons/aristolochic)  
Toxic: yes

> **Caution.** 

## What did Canale use it for?

In the cockerel, the bath, the oil; as an amulet (chs. 6–7, 9–10).

## What does modern science say?

Named for its use in childbirth. It contains aristolochic acid, which causes kidney failure and cancer, and is banned or restricted in herbal medicines in many countries.

## Pharmacognosy and toxicology

- **aristolochic acid I**: 
- **aristolochic acid II**: 

**Mechanism.** The aristolochic acids are activated in the kidney to compounds that bind DNA; the adducts cause a characteristic mutation and kill the tubule cells.

**Dose.** Cumulative; the Belgian patients took about 200 g of the herb over a year.

**Standing.** Banned in the European Union, the United States (2001), and most of Asia; the FDA warns against every product containing *Aristolochia*.

## What lore surrounds it?

Folkard derives the old English name “from its reputed remedial powers in parturition—probably first suggested by the shape of the corolla—whence also its Greek name, from aristos, best, and locheia, delivery,” and adds from Pliny that “if the expectant mother desired to have a son, she employed Aristolochia, with the flesh of an ox.” Certain species are “renowned, in some European countries, for having a wonderful influence over fishes and serpents”; the snake jugglers of Egypt “are believed to stupefy these reptiles by means of a decoction distilled from the plant,” and “Apuleius recommends the use of Aristolochia against the Evil Eye.”

Grieve adds that Aristolochia sempervirens “is said to be used by the Arabians as a remedy against the poisonous effects of snake-bite,” and the serpentary of North America “as an alexiteric and for the bites of mad dogs.”

## What did the older authorities say?

**The name.** Greek *aristolochia*, “best for childbirth”: its curved flower was read as a sign of the womb, and it was given to hasten labor.

## Sources

- Folkard, R. (1884). *Plant Lore, Legends, and Lyrics*, “Aristolochia.” Project Gutenberg #44638.
- Grieve, M. (1931). *A Modern Herbal*, “Birthwort.” botanical.com/botanical/mgmh/b/birthw44.html
- Vanherweghem, J.-L., et al. (1993). *Lancet* 341.
- Hoang, M. L., et al. (2013). “Mutational signature of aristolochic acid exposure as revealed by whole-exome sequencing.” *Science Translational Medicine* 5.

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*Round birthwort.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-01. The Thinking Press. https://thethinkingpress.org/materia-medica/round-birthwort

Historical description, not medical advice.