This prospective cohort will evaluate the ovarian function of 210 ENG users during the three years beyond the FDA approved duration. Participants enrolled in the current study, EPIC (Evaluating the Prolonged Use of IUD and Implant for Contraception, NCT02267616), will be contacted via telephone, screened and scheduled to enroll in person. After the signed consent is obtained participants will be asked to complete a brief questionnaire on demographic information and bleeding patterns. Participants will undergo a blood draw to assess serum etonogestrel and serum progesterone levels.
Follow up visits will include a weekly blood draw for three weeks to assess serum progesterone levels. Participants will also complete a bleeding diary to assess daily bleeding patterns for the 30 day study period.
The investigators will enroll participants at seven time points; at method expiration (3 years of use), and in six-month intervals through six years of use.
