In the middle ages and earlier it was thought that the uterus migrated around the body. If the woman, whose natural disposition tended toward wet humors, did not receive enough moisture (from sex) her uterus would dry up and go around the body searching for water. If it attached to her liver, she would lose her voice; if it attached to her head, it would make her sleepy, and so on. This condition was called hysteria and it explained nearly anything that could be wrong with a woman. The cure was sex and, in later centuries, the steam-powered vibrator.
In keeping with the (apparently quite old) wandering uterus theory, Plato called the uterus an "indwelling creature desirous of child-bearing" that wanders when it is "distressed and sorely disturbed." Other writers debated whether the uterus was an animal or just a part of the human body.
The anatomist Galen rejected the idea that the uterus could even migrate far enough to attach to the diaphragm, because the stomach is in the way. Galen had a different idea about the uterus: that the female reproductive tract is the same as the male's, only inside-out and thus defective. In the system of humors, females were associated with cold and wet whereas males are hot and dry:
Now just as mankind is the most perfect of all animals, so within mankind the man is more perfect than the woman, and the reason for his perfection is his excess of heat, for heat is Nature's primary instrument. ...
The woman is less perfect than the man
in respect to the generative parts. For the parts were formed within her when she was still a fetus, but could not because of the defect in the heat emerge and project on the outside.
Galen referred to the ovaries as the "female testes" and held the view that conception occurred when the "female semen" met up with the male semen. Galen also believed that the "semen" for boy babies came from the right ovary while that for girls came from the left, because the right ovary has a better and stronger blood supply, and is "in a straight line with the liver".
Oddly enough, a sex manual called "Aristotle's Masterpiece" from the 1600's (which claimed to be written by Aristotle and which was in print from at least 1684-1814) gives a description that is eerily close to the truth, though at the time nobody had seen (or thought to look for) the female ovum:
(T)esticles in women do not afford seed, but are two eggs, like those of fowls; neither have they any such office as those of men but are indeed an ovarium, a receptacle for eggs ... and the truth of this, say they, is so plain that if you boil them, they will have the same taste color and consistency, with the taste of birds eggs.
References and further reading:
Bullough, Vern L. Sex, Society, and History. Science History Publications, New York, 1976.