You assume that because girls in the US menstruate at 12-13, that this is universal, and has always been the case. In fact, throughout history the age of menarche was more like 16, and remains so in many places, possibly due to poor nutrition. Thus, marriage at age 17 or so made sense, the girl wasn't nubile before that.
Further, even if a girl menstruates at 12, that doesn't make her a good candidate for motherhood. The uterus and the pelvic structure aren't ready for the tremendous burden of childbearing.
Your point, though, that the best age, physically, for childbearing is far younger than say, 30, is a good one, and I don't have a good answer for it. It is very difficult to integrate being the mother of a young family with having a career. |
