It hasn't seemed fair for a long time, either. The BIble even chalks it up to Eve eating the apple in the Garden of Eden, bringing the curse of childbirth pain upon women forever after. That was the way the ignorami explained things in those days. Thanks to modern science, we know that childbirth was an evolutionary development from our apelike ancestors, who had (and needed) much smaller skulls to accommodate their much smaller brains. But big brains are our primarily evolutionary advantage, so they grow just about as big as they can in the womb -- any bigger and they'd kill the mother at birth, which wouldn't provide long-term survival advantages -- and then KEEP growing for years afterward. Critters for whom the brain is just a tag-along don't have this kind of problem.