1 Planned Parenthood League of Massachusetts, Boston, MA, United States.
2 Cochrane Fertility Regulation Review Group, Portland, OR, United States; Center for Health Research, Kaiser Permanente Evidence-based Practice Center, Portland, OR, United States.
3 Center for Health Research, Kaiser Permanente Evidence-based Practice Center, Portland, OR, United States; Department of OB/GYN, Oregon Health & Science University, Portland, OR, United States.
4 Center for Health Research, Kaiser Permanente Evidence-based Practice Center, Portland, OR, United States; Department of OB/GYN, Oregon Health & Science University, Portland, OR, United States. Electronic address: edelmana@ohsu.edu.