The other thing is that you're not always going to welcome pregnancy, so if you get fertility-impaired for the "minor and transitory" time period of ages 28 through 30, or whenever your romantic status and job ststus lined up right to make kids seem like a good move, you might be effectively nullified, reproductively speaking. I'm not making a judgment--just saying that in the real world, a couple of years of infertility might mean you never have kids. Reading *The Children of Men* right now and quite struck by the parallels.