A cohort study to Evaluate the contraceptive effectiveness of Sino-implant (II) during the 3rd and 4th years of use in Chinese women

A Study to Evaluate the Contraceptive Effectiveness during the Third, Fourth and Fifth Year of Sino-implant (II)Use and the Pharmacokinetics (PK) over Five Years of use in Chinese Women

Population: A total of 590 Chinese Sino-Implant (II) users between 20and 44 years of age enrolled in one of four prospective cohorts:

Cohort 1: n=20 women with insertion dates 3-5months prior to enrollment and followed for 2-6 months Cohort 2:n=20 women with insertion dates 9-11 months prior to enrollment and followed for 2-6 months Cohort 3: n=250 women with insertion dates 21-24 months prior to enrollment and followed through month 36 Cohort 4:n=300 women with insertion dates 33-36 months prior to enrollment and followed through month 6

Study Duration: 33 total months in the field: 3 months of participant recruitment(all cohorts); up to 27 months of pregnancy monitoring and PK blood sampling in Cohort 4 (up to 15 months in Cohort 3 and 6 months in Cohort 1 and Cohort 2);and 3 months of close-out activities.

For secondary PK outcomes, blood samples will be taken 2 to 6 months apart from each woman in Cohort 1 and Cohort 2; at enrollment, month 30 and month 36 from the first 20 consenting women in Cohort 3; and at enrollment and months 42, 48, 54, and 60 from the first 30 consenting women in Cohort 4.

Primary Objective: To evaluate the contraceptive effectiveness of Sino-implant (II) during the third and fourth years of use

Secondary Objectives:

1. To evaluate the contraceptive effectiveness of Sino-implant (II) during the fifth year of use.
2. To characterize the total and free levonorgestrel (LNG) plasma concentration-time profiles over five years following Sino-implant (II) insertion
3. To characterize the sex hormone binding globulin (SHBG) serum concentration-time profile and its relationship to total LNG levels over five years following Sino-implant (II) insertion

Inclusion Criteria:

• Have a confirmed Sino-implant (II) set in place;
• Have a confirmed contraceptive implant insertion date consistent with the criteria for the cohort she is to be enrolled in;
• Be aged between 20 and 44 years, inclusive;
• Not wish to become pregnant in the next year;
• No desire to get implant removal within the next year;
• Be able to understand the information given to them and to make personal decisions on whether to participate or not in the study;
• Consent to participation and sign an informed consent form;
• Agree and be able to return to the clinic for follow-up visit(s).

Exclusion Criteria:

• Acute liver disease or cirrhosis by self-report;
• Benign or malignant tumor of the liver by self-report;
• Use of rifampicin, and/or anticonvulsants (barbiturates, phenytoin, phenobarbital, carbamazepine, oxcarbazepine, primidone, topiramate), and/or herbal products containing St. John's wort (Hypericum perforatum) by self-report;7
• Use of medications containing LNG or other hormones that impact LNG or SHBG disposition, e.g. treatment with LNG or oral contraceptives for bleeding disturbances by self-report;
• Known HIV-positive status by self-report;
• Any condition (social or medical) which in the opinion of the Investigator would make study participation unsafe, would interfere with adherence to study requirements, or complicate data interpretation.

Study Population: Women who have received contraceptive implants from the Tongxiang, An Yang, Lingbao, and Lushi Family Planning Service Stations.