Exclusion Criteria: 1) are pregnant; 2) have a contraindication to hormonal contraception; 3) are unwilling to use NuvaRing as their contraceptive method; 4) are currently using any hormonal contraceptive or have used one within past 2 months; 5) have used emergency contraception in the past 7 days; 6) have had unprotected intercourse in the past 10 days; 7) have untreated Gonorrhea or Chlamydia; or 8) are unable to give informed consent because of psychiatric or cognitive problems.