My research (and I do get sucked into research!) has led me to an online e-book called Women and the Practice of Medical Care in Early Modern Europe, 1400-1800. http://www.barnesandnoble.com/w/women-and-the-practice-of-medical-care-in-early-modern-europe-1400-1800-leigh-whaley/1023351355?ean=9780230282919&itm=1&usri=women+and+the+practice+of+medical+care+in+early+modern+europe
Many of the women accused of practicing witchcraft were traditional healers, who used herbal medicine and in some cases practiced midwifery. For a long time, women practiced in the medical profession, but in the late Middle Ages along came official medical schools in universities, where women were barred from studying. Accusing traditional, unlicensed healers of witchcraft and burning them at the stake was quite a way to decrease the competition.
I visited Massachusetts in the fall (including a day in Salem) and although I have previously read up to some extent in the Burning Times, since then I've gotten sucked into doing research on the topic and incorporating it into my fantasy fiction. My sources include:
Barstow, Anne Llewellyn. Witchcraze: a New History of the European Witch Hunts. Pandora, NY: 1994.
Demos, John. The Enemy Within: a Short History of Witch-Hunting. Penguin Books, NY: 2008.
Ehrenreich, Barbara, and Deirdre English. Witches, Midwives, and Nurses: a History of Women Healers. Second Edition. Feminist Press, NY: 2010.Illes, Judika. The Element Encyclopedia of Witchcraft. HarperElement, London: 2005.
Russell, Jeffrey B. & Brooks Alexander. A History of Witchcraft: Sorcerers, Heretics, and Pagans. Second Edition. Thams & Hudson, NY: 2007.
Whaley, Leigh. Women and the Practice of Medical Care in Early Modern Europe. Palgrave MacMillian, NY: 2011.