The fact that abortion is one of the most controversial topics in America, liberal judges tend to be more favorable of abortion. Conservative judges tend to be more critical of abortion. Thus, depending the judge nominated to the SCOTUS, the court will be influenced by that judge.
For example, Justice Amy Conney Barret was recently nominated to the SCOTUS (following the death of late Justice Ruth Bader Ginsburg) and now has made the court significantly more balanced towards conservatism.
