Atlas Obscura explains that in Ming and Qing Dynasty China (1368-1911), physicians could not directly examine the bodies of upper class women. Even directly speaking about the bodily conditions was unacceptable, so the women would point to relevant areas on medical dolls, such as the one pictured above. The doctors would diagnose maladies and provide treatments based on this indirectly communicated information.
The author's source is a scholarly journal article published in 1952. I found this sourcing insufficient, so I searched for other, more recently and clearly referenced sources and came across this webpage by Yuewei Yang, a student at the Royal College of Physicians in London.
Yang is deeply skeptical of the historical claim and concludes that these dolls were probably for sale to gullible Westerners who had exotic (and erotic) views of Chinese culture. For one thing, most of the dolls are posed in rather . . . sensual ways. The one pictured above isn't even the most suggestive example that I've seen. Yang also points out that most of the surviving dolls are found in the West (the one above is in Kansas), not in China.
Finally, during the Ming Dynasty, elite ladies and physicians weren't allowed to communicate in any form at all. Rather, male relatives would ferry messages back and forth between female patients. Thus a medical doll would be unnecessary.
It's clear that more (hopefully grant-funded) research is necessary in this field.
-via Messy Nessy Chic | Photo: Clendening History of Medicine Library and Museum