1. Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341‐3717, USA
2. Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341‐3717, USA
3. Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341‐3717, USA
4. Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341‐3717, USA
5. Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341‐3717, USA
6. Department of Gynecology and Obstetrics, Emory University School of Medicine, Atlanta, GA 30303, USA
7. Graduate School of Public Health, Medical Science Campus, University of Puerto Rico, PO Box 365067 San Juan, Puerto Rico 00936‐5067, USA
8. Graduate School of Public Health, Medical Science Campus, University of Puerto Rico, PO Box 365067 San Juan, Puerto Rico 00936‐5067, USA
9. Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341‐3717, USA