Defunding Planned Parenthood causes more abortions, not less. Planned Parenthood provides contraception to a lot of low-income women when they don't think they are financially able to support more children. They provide a lot more contraception than abortions.

The only thing that could cause more abortions than defunding Planned Parenthood would be to take away the subsidies that low-income women rely on to buy health insurance, and make them even more financially insecure and even more convinced they couldn't care for a child. 

Oh, wait, they're doing that too.