Trotula of Salerno has been the subject of a smear campaign lasting roughly one thousand years. Possibly. Or possibly she never existed.
In the 11th century, Salerno was the place to be if you wanted to be a physician. It had what some claim is the world's first real medical school. It had hospitals and doctors that people would travel huge distances to visit. And it had each of those because of a solid scholarly tradition. Many physicians from Salerno wrote medical treatises, but the most famous is Trotula.
Trotula wrote medical books meant to instruct male doctors regarding the medical care of women. Since the vast majority of formally educated doctors were men, and religious and legal taboos often prevented them from practicing on women, few knew anything about gynecological problems. Trotula sought to fix that. She wrote two major books. One covered gynecological and obstetric problems. It included, controversially, the idea that sometimes men were the biological cause of conception problems, instead of just women. The other was more of an advice book for women, and dealt with cosmetic issues, from ways to treat puffy eyes to ways to soothing skin diseases. The two books represented a massive store of knowledge that male physicians wouldn't have had access to if Trotula hadn't studied to be a doctor, and picked up her pen.
Or were they books written by male physicians under a female pseudonym to avoid legal trouble? Since the books were first circulated, there have been rumors that the books were actually written by male doctors. Academic women were rare, and a woman receiving formal medical education would have been even more so. There was also a faction of people who believed that women were not capable of producing intellectual work.
These arguments came to a head in the 1500s, when historians and doctors announced that there never was a Trotula in the first place. Since then, she's become a semi-mythical figure. Even those who believe in her existence sometimes doubt her work. The few facts that anyone has pertaining to the woman - that she may have been from a noble family, that she may have had a physician for a husband or a son - have been used to attribute the book to male relatives who used her name as a cover.
Most historians today believe that Trotula did exist, and that she did write both treatises. So if you ever want to dye your hair or treat snake bite while honoring an early female scientist, look up her books!