My wife has delivered babies to 12 year olds who were impregnated when they were 11, so perhaps it's time to rethink your time table.
You seem to be assuming that these 11-year-olds did not have sex education in their schools, and would not have been pregnant if they had. In fact, research indicates that students given classroom sex education are more likely to be sexually active, not less likely.
Perhaps it's time to rethink serious jail time for people (of any gender) who screw 11-year-olds.