Sparta
Young Spartans boys were taken from their homes at the age of seven to begin a military life.  The Spartans became soldiers at age 20, citizens at age 30, and retired at age 60. Men trained hard to become warriors of the Spartan army.  Women were encouraged to keep healthy so that they could produce healthy, fit babies to grow up to be strong.  Spartans saw little moral value in the concept of childbirth; unless the child was fit to become a Spartan, he would die.