10/03/2024
"The rhombus of Michaelis (sometimes called the quadrilateral of Michaelis) is a kite-shaped area that includes the three lower lumber vertebrae, the sacrum and that long ligament which reaches down from the base of the scull to the sacrum.
This wedge-shaped area of bone moves backwards during the second stage of labour and as it moves back it pushes the wings of the ilea out, increasing the diameters of the pelvis.
We know it’s happening when the woman’s hands reach upwards (to find something to hold onto, her head goes back and her back arches.” (Wickham and Sutton 2002).
Jean Sutton and I first wrote about the rhombus of Michaelis in 2002.
We weren’t the first to notice it.
Midwives from around the world had been aware of it and discussing it for many years.
Some talked about “the opening of the back,” while others described the shape, and discussed it in the same sentence as they talked about purple lines and cold feet.
That is, the embodied wisdom of birth.
Since we wrote about it, many thousands of midwives and birth workers have learned about this physiological feature of birth from our article and the conversations that it has sparked.
The original article is available on my website.
Yes, it’s one of those named by and for a man, and that’s not OK. But if we change the article title then people won’t be able to find it.
I’m re-sharing the link to the article today in the hope of sharing the information more widely.
You can read it at https://www.sarawickham.com/articles-2/the-rhombus-of-michaelis/
I hope you’ll find it useful.
Yes, please feel free to share and repost this social media post, with the pic, words and credit intact.
Thanks to my friends at for letting me reshare their image