title: The Mirena levonorgestrel system.
abstract: The levonorgestrel intrauterine system is a safe, efficacious, long-term contraceptive device. Additionally, it results in a decrease in the volume of menstrual blood loss in women with normal periods and those with menorrhagia. It may also have a role in the treatment of other benign gynecological disorders, such as adenomyosis or endometriosis, and it has been advocated as a means of delivering progestogen to the endometrium as part of combined hormone replacement therapy. Despite the beneficial effect on menstrual volume, compliance is sometimes limited by breakthrough bleeding during the first months of use. The precise mechanism of this bleeding is unclear, but it may be related to a direct effect of levonorgestrel on endometrial vascular development. Detailed counseling is crucial to explain this anticipated side effect in order to reduce unnecessary discontinuation of treatment.
authors.affiliation: Department of Obstetrics and Gynecology, Southern General Hospital, South Glasgow University Hospitals NHS Trust, Govan, Glasgow, UK.
authors.forename: C Jay
authors.initials: CJ
authors.lastname: McGavigan
authors.forename: Iain T
authors.initials: IT
authors.lastname: Cameron
mesh_terms: D003271:Contraceptive Agents, Female / Q000008:administration & dosage / Q000493:pharmacokinetics; D004717:Endometrium / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D006801:Humans; D007436:Intrauterine Devices, Medicated; D016912:Levonorgestrel / Q000008:administration & dosage / Q000494:pharmacology*; D015337:Multicenter Studies as Topic; D016032:Randomized Controlled Trials as Topic
chemical_list: D003271:Contraceptive Agents, Female; D016912:Levonorgestrel