China tried that and you know what happen? They have more men than woman which leaves alot of men single for life and alot of baby girls were killed at birth or left for dead.
I would argue that what happened in China was less of an environmental activist push and more to have an economical and societal impact. You have to pay out the dowry to your daughter's husband and his family and families worrying about money worry less when there's only one kid to clothe and feed.
China *bans gay*