A highly effective single rod contraceptive implant is now available for use in the US. Delays in the insertion of the device until later in the postpartum period may negatively impact initiation rates. The objective of this study is to compare outcomes of early postpartum insertion (prior to postpartum hospital discharge) of the etonogestrel-releasing contraceptive implant with routine postpartum insertion at 4-8 weeks after delivery. Primary outcome of interest will be time to lactogenesis. Secondary outcomes will include rates of breastfeeding supplementation, infant growth, vaginal bleeding patterns, incidence of side effects, time to resume sexual intercourse after delivery, and incidence of missed routine postpartum follow-up. In addition, a subset of patients who randomize to early postpartum insertion will have expressed breastmilk ascertained for nutrient composition.

This is a randomized controlled trial. Participants will be assigned with equal probability to 1 of the 2 test groups using computer-generated random numbers in blocks of varying sizes. Allocation concealment will be assured by enclosing assignments in sequentially numbered, opaque, sealed envelopes. Envelopes will be opened sequentially and only after the participant's name and study number are written on the envelope. Follow-up and data collection for participants in each group will be identical. Outcome assessors and data analysts will be blinded to treatment arm.

STUDY PROCEDURES:

Inclusion/exclusion criteria will be verified and consent obtained. The patient will be notified of the results of randomization and the physician able to perform insertion will be contacted to perform the insertion. All insertions will be performed by physicians who have completed Implanon® insertion training. If the patient randomizes to standard postpartum insertion, she will be given a clinic appointment in 4-8 weeks for the insertion procedure.

Lactogenesis time will be documented by maternal perception, as described and validated by Chapman et al16. If lactogenesis has not occurred prior to hospital discharge, the patient will receive daily phone calls from study personnel until lactogenesis can be confirmed and recorded. Contact information for the patient, as well as for two friends or relatives who will know how to reach her will be obtained and verified prior to discharge. Participants will be given a reminder card for the telephone calls from the investigator and a postpartum visit appointment. Patients will be instructed to contact the investigators immediately for pain, excessive bleeding, difficulty with breastfeeding, or other concerns. Patients will be given a log book ("diary") to record breastfeeding parameters including use of supplementation, infant weights, side effects, return to sexual intercourse, contraceptive method use, and days of bleeding for the study follow-up period.

Clinical follow-up will be as follows. Postpartum telephone calls or visits to collect additional data will occur as needed for up to 5 days following hospital discharge, at 2 weeks, 4-8 weeks, and 3 and 6 months postpartum. Information obtained at these points will include: breastfeeding status and parameters, collection of record of infant weights (birth, 4-8 weeks, and 6 months), reminders to keep weekly diary, collection of diaries (6 month visit), resumption of sexual activity, use of contraceptive method, and satisfaction with contraceptive method. Patients randomized to early insertion will be asked to give a milk sample for analysis at their 4-8 week visit. Table 1 describes the contact points with the subject for collection of data. Contact will be either by telephone or at clinic visits.

Inclusion Criteria: Patients on the postpartum ward at University Hospital will be offered inclusion in the study if they are:

• healthy,
• 18-40 years old,
• delivered a healthy term infant,
• intend to breastfeed,
• desire Implanon as their method of contraception, and
• agree to be randomized to early versus standard postpartum insertion.

Exclusion Criteria:

• obstetric complications including anemia with hematocrit<30,
• transfusion,
• infection,
• severe pregnancy induced hypertension,
• prolonged hospitalization,
• coagulopathy,
• liver disease,
• undiagnosed genital bleeding,
• or other relative contraindication to Implanon® insertion (known or suspected pregnancy, known, suspected, or history of breast cancer, or hypersensitivity to any of the components in Implanon®).
• Women taking drugs that are potent inducers of hepatic enzymes will also be excluded, including barbiturates, griseofulvin, rifampin, phenylbutazone, phenytoin, carbamazepine, felbamate, oxcarbazepine, topiramate, modafinil, protease inhibitors, and herbal products including St. John's Wort.

Adverse event data was collected for 6 months from delivery.

Limitations:Study was not blinded & early insertion was allowed as late as 3 days postpartum. Insertion on postpartum days 1-3 was allowed so long as lactogenesis had not already occurred to mimic normal clinical practice & improve generalizability.