Contraception - Subdermal implants

The Norplant system was a six-rod progestin implant that was implanted in the skin of the arm and released 50 to 80 mg levonorgesterel the first year and 30 and 35 mg per year for each of the following four years. In 2000, the manufacturer issued an advisory that the contraceptive efficacy of certain lots of the implants could not be guaranteed, and it was withdrawn. Implanon™ was approved in 2006. It is a single rod progestin subdermal implant that is about the size of a match stick. It continually releases a steady dose of progestin (etonogestrel) for up to three years. Its effect is quickly reversible. A woman’s fertility returns within 24–72 hours of removal. Its primary mechanism of action is to inhibit ovulation although it also increases the viscosity of cervical mucus. It can be used for lactating women after the fourth postpartum week.43 It is placed in the groove between the biceps and triceps muscles and can only be inserted and removed by clinicians who complete a formal training program. Efficacy Six pregnancies have been reported in 20,648 cycles. Side effects Side effects include irregular menses and headache. Bleeding irregularities usually decrease over the first six to twelve months and after that time most women experience amenorrhea. At the end of the first year the mean cumulative weight gain was 2.8 pounds and by the end of the second year 3.7 pounds. Less common side effects are acne, change in appetite, change in libido, ovarian cysts, discoloration or scarring of the skin over the implant, dizziness, hair loss, headache, nausea, nervousness, pain at the insertion site or sore breasts. Contraindications Contraindications include active liver disease, active thrombophlebitis, known or suspected breast cancer, undiagnosed abnormal gynecological bleeding, pregnancy, or hypersensitivity to the drug. Some medications may make Implanon™ less effective. These include barbiturates, griseofulvin, rifampin, phenylbutazone, phenytoin, carbamazepine, felbamate, oxcarbazepine, topiramate, and modafinil as well as possibly herbal remedies such as St. John’s Wort. Interested clinicians should register at the website http://www.implanon-usa.com/hcp/index.asp?C=571 37391742296759259&OrgDom=www.implanonusa.com or http://www.implanon-usa.com/hcp/index.asp?svar qvp2=0 for information on training.

Posted in: Contraception,Health