On-topic (sorta) : We've done a lot on the one child policy in China, quite a lot of the time its a bad idea. When a girl is born, they cannot continue the family name and therefore the baby girl is killed/abandoned in favour of a boy. This then means if every family wants there to be a boy born (and this next bit is not true) and if every family is willing to abandon a baby girl, you're going to get a major shortage of women in the next few generations.
Thats funny, i just happened to stumble on to this the other day.
NBC: China begins to face sex-ratio imbalance - World news- msnbc.com