What's stopping young Liberal women from getting their tubes tied? If they don't want any kids, and don't want to have to worry about birth control, or getting a "hard to get" abortion, just get their tubes tied. Less Liberal babies is not a bad thing. They can naturally become extinct.
Free tubal ligation and vasectomies should be on the Liberal voting platform.
Heck, crazy Liberal parents want to change their kid's gender anyways. As soon as they reach puberty, they should just get them neutered.