It's a small price to pay for preserving the future. The government should eliminate tax breaks for children, either altogether or after a family already has two kids.
Tax breaks encourage population growth by artificially reducing the cost of having children.
Likewise, welfare subsidies that increase with family size should be dropped as soon as possible. A family cap law in New Jersey has shown good results. Pregnant teenagers should be denied all government assistance unless they identify the fathers and are subject to the same standards of parental competency as adoptive parents. The real world does not allow for single-issue panaceas. Kids need to be educated about overpopulation beginning in the 5th or 6th grade.