Material and Method
The participants were recruited from The Family Planning Clinic at King Chulalongkorn Memorial Hospital. The protocol was approved by the ethics of the institution.
After giving their written informed consent,the participants had to meet the following inclusion criteria: healthy women aged 16-20, who were sexually active and at risk of pregnancy, had regular menstrual cycles and at least one normal menstrual cycle, body weight less than 90 kg and no use of any other steroid hormonal therapy at least 3 months before beginning the present study. Exclusion criteria included pregnancy and lactation, any acute or chronic liver disease, history of significant cardiovascular, hepatic, renal or thromboembolic disease, hypertension > 140/90 mmHg, metabolic disturbance or any malignant tumor, history or presence of dermal hypersensitivity, undiagnosed abnormal uterine bleeding, active cigarette smoking,and alcohol or drug abuse.
Before the start of the contraceptive patch,each woman underwent a through general medical and
gynecological examination including a cytological smear. The participant assigned to receive 3 cycles of
contraceptive patch and follow-up every cycle or every month. Participants had a diary card on which to
record bleeding per vagina application site reaction,adverse event, body weight and blood pressure. Participants were asked about their menstrual pattern and about any side effects or any concerns with this contraceptive patch. They were also asked specific questions related to patch application such as experience of detachment, peeling and adherence to patch application schedule. Data were analyzed using mean,standard deviation, percentage and student’s t-test. Ap-value of less than 0.05 was considered significance change.
Patch description and use
The Ortho Evra™patch is designed to deliver 20 µg of ethinyl estradiol (EE) and 150µg of
Norelgestromin daily. Participants were instructed to apply the patch to the buttock, upper outer arm, lower abdomen, back and upper torso (exclusion breast). A new patch could be applied near,but not on old sites.Participants were instructed to maintain their usual activities during patch use, including bathing and
swimming. Participants were advised to apply the patch on the same day of each week (one patch per
week) for three consecutive weeks followed by a patchfree week. Each course was repeated monthly for the duration of the 3-month study period. In the event of patch detachment, a new patch was to be applied
immediately and worn for the remainder of the week.