title: Implant contraception.
abstract: The experience of 6 million Norplant users has led to several more advanced implants. Implanon is a single-rod implant system containing a low androgenic progestin and requires 1 to 2 minutes for insertion and removal. Like other implants, Implanon prevents pregnancy by changing the character of the cervical mucus and interfering with luteal function. Unlike Norplant, though, Implanon is designed to prevent ovulation for the full duration of use. Implant contraception has several advantages over other types of contraception including high efficacy, minimal required maintenance, absence of estrogen, and rapid return of fertility after discontinuation. Implants can be a good choice for adolescents; women with hypertension, diabetes, anemia, endometriosis, or other medical problems; and women who are breast-feeding. Irregular bleeding is the most common adverse effect of implants and can be treated with several medication regimens. Preinsertion counseling, however, is the most important factor in ensuring satisfaction with implants. Unfortunately, no implant system is currently available in the United States since August 2000, but Implanon is expected to reach the U.S. market within the next 2 years.
authors.affiliation: Center for Reproductive Health Research and Policy, Department of Obstetrics, Gynecology, and Reproductive Sciences, San Francisco General Hospital, University of California, San Francisco, California 94110, USA.
authors.forename: K R
authors.initials: KR
authors.lastname: Meckstroth
authors.forename: P D
authors.initials: PD
authors.lastname: Darney
mesh_terms: D002582:Cervix Mucus / Q000187:drug effects; D002986:Clinical Trials as Topic; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000191:economics / Q000494:pharmacology; D003376:Counseling; D017135:Desogestrel; D004343:Drug Implants / Q000008:administration & dosage*; D004717:Endometrium / Q000187:drug effects; D005260:Female; D006801:Humans; D016912:Levonorgestrel / Q000008:administration & dosage / Q000494:pharmacology; D008535:Megestrol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D009653:Norprogesterones / Q000008:administration & dosage / Q000494:pharmacology; D010060:Ovulation / Q000187:drug effects; D017060:Patient Satisfaction; D011247:Pregnancy; D045167:Progesterone Congeners / Q000008:administration & dosage* / Q000191:economics / Q000494:pharmacology; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D014753:Vinyl Compounds / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D003271:Contraceptive Agents, Female; D004343:Drug Implants; D009653:Norprogesterones; D045167:Progesterone Congeners; D014753:Vinyl Compounds; C047637:nomegestrol; C044815:etonogestrel; D016912:Levonorgestrel; C029167:ST 1435; D017135:Desogestrel; D008535:Megestrol