2.4.1- Type of study: A prospective observational cohort study. 2.4.2- Study Setting: Assiut General Hospital . 2.4.3- Study subjects:
- Women who delivered vaginally or by caesarean section at term (≥37 weeks of gestation).
- Age between 18 and 45 years.
- Desire to use the etonogestrel subdermal implant (Implanon-NXT®) as a method of contraception.
- Willing to provide written informed consent prior to enrollment.
- Exclusion Criteria:
- Known or suspected current pregnancy.
- Postpartum hemorrhage requires uterotonic therapy at the time of planned insertion.
- Chorioamnionitis, puerperal sepsis, or any active pelvic or systemic infection at the time of insertion.
- Not eligible for Implanon-NXT insertion according to WHO criteria
- Known hypersensitivity to etonogestrel or any component of the implant device.
- Inability or unwillingness to provide written informed consent.
C. Sample Size Calculation:
Based on determining the main outcome variable, the estimated minimum required sample size is 90 women (45 women per group).
The sample size was calculated using G*Power software version 3.1.9.4, based on a previous randomized controlled trial, the proportion of abnormal bleeding was estimated to be 51.1% in the immediate insertion group and 23.8% in the delayed insertion group .
The main statistical test used was the Chi-square test to detect the difference between two independent proportions.
An equal classification ratio (1:1) between the two groups was assumed. A significance level (α) of 0.05 and a study power of 80% were considered.
To compensate for possible loss to follow-up, an additional 10% was added, resulting in a final sample size of 100 women (50 per group).
2.4.4 - Study tools (in detail, e.g., lab methods, instruments, steps, chemicals, …): During the screening, all eligible postpartum women will be assessed, the study explained, and written informed consent obtained from each participant.
Postpartum women aged 18-45 years who delivered at term and desire long-acting reversible contraception.
Menstrual/bleeding calendars will be used to record bleeding days as recommended by the World Health Organization (WHO) Belsey definitions of bleeding patterns with contraceptive use .
Eligible women will be recoded in and classified into two cohorts according to the timing of
- (immediate postpartum insertion, minutes 72 hours after delivery)
- (delayed postpartum insertion, at 4-6 weeks postpartum).
II. Initial evaluation (before insertion):
- Clinical evaluation: Detailed history (age, parity, obstetric history, medical and drug history, allergies), vital signs, general and local examination.
- Investigations: Complete blood count, coagulation profile, and liver function tests.
- Breastfeeding assessment: initiation of breastfeeding documented before insertion.
III. Implant Insertion Procedure A. Pre-Insertion Requirements
Before inserting IMPLANON-NXT®, the trained clinician must confirm all of the following:
- The woman is not pregnant and has no contraindication to the use of IMPLANON-NXT®.
- A relevant medical history and physical examination, including a gynecologic examination, have been completed.
- The woman has been counseled on the benefits, risks, and expected changes in menstrual bleeding patterns associated with the implant.
- The woman has received and reviewed the Patient Labeling included in the packaging.
- Written informed consent has been obtained and filed in the woman's medical record.
- The woman has no known allergy to the antiseptic or local anesthetic agent to be used during the procedure.
B. Required Equipment
- Examination table
- Sterile surgical drapes and sterile gloves
- Antiseptic solution and surgical marker
- Local anesthetic (e.g., 1% lidocaine), needles, and syringe
- Sterile gauze, adhesive bandage, and pressure bandage
- Sterile preloaded disposable IMPLANON-NXT® applicator (inspect packaging for breaches of integrity before use)
C. Insertion Procedure Organon USA Inc. IMPLANON-NXT® (etonogestrel implant)
IV. FOLLOW UP. Follow-up visits will be for 6 weeks, 3 months, 6 months, and 12 months after insertion with the following assessments .
II. Post-insertion follow up:
Follow-up visits will be for 6 weeks, 3 months, 6 months, and 12 months after insertion with the following assessments:
A. Clinical Assessment:
- Implant site evaluation: Check for correct position, displacement, infection, or other local complications.
- Bleeding pattern assessment: Using WHO Belsey bleeding definitions.
- Breastfeeding status: Exclusive, partial, or cessation of breastfeeding, and time to cessation.
- Side effects: Headache, mood changes, weight change, acne.
- Patient satisfaction: Assessed using a validated Likert-scale questionnaire.
- Unintended pregnancy: Confirmed by urine or blood pregnancy test at each visit if clinically indicated.
- Contraceptive continuation: Document whether the implant remains in situ or has been removed (and reason for removal).
B. Laboratory investigations:
Blood pressure, Body weight / BMI, Urine pregnancy test and complete blood count at 3 months and 6 months post-insertion to monitor for anemia.
C. Transvaginal Ultrasound Doppler of the Uterine Artery
Evaluated at each visit (6 weeks, 3 months, 6 months, and 12 months):
- Size of uterus - three dimensions measured (length × anteroposterior × transverse diameter in cm) as an indirect marker of uterine involution
- Endometrial thickness - measured in the sagittal plane at the thickest point (mm)
- Uterine artery Pulsatility Index (PI) measured bilaterally; mean UtA-PI calculated
- Ovaries Ovarian size, Ovarian volume, Follicular activity, Ovarian cysts, Evidence of ovarian suppression and any adnexal pathology .
