Congenital malformations of the uterus are not rare; they affect as much as 7% of women. When I was studying to be a nurse, I wanted to know more about the causes, effects, and nursing implications of these malformations, also known as "müllerian anomalies," and so researched the topic for a paper.
My interest was professional (I liked OB nursing) and personal, since I had found out the difficult way that I had a uterine anomaly, myself. These anomalies tend to be like buried WWII artillery shells . . . you don't know about them until something tragic—usually pregnancy loss—happens. A few might be discovered before a woman attempts pregnancy, but most of the time, painful menstrual periods are the only clue.
And who doesn't bitch about cramps from time to time?
In the interest of plunking one more anchovy onto the pizza that is DK4, and in the spirit of knowledge, I am subjecting you to this paper, minus the footnotes. If you read on, you even get to see my x-rayed innards, before and after surgery to correct the problem.
Among my support community for people who have this anomaly, the recent, undead "criminalizing miscarriage" issue sparked a lot of jokes about jail time, muttered darkly. And what would Michelle Bachman think of a woman unable to produce children as easily as she did?