Levonorgestrel-releasing intrauterine device

An intrauterine device (progestasest) that releases low amounts of progesterone locally is available for insertion on a yearly basis. Its effectiveness is considered to be 97-98% contraceptive action probably is due to local effects on the endometrium. Another intrauterine device (MIRENA) releases levonorgestrel for up to 5 years. It again is thought to act primarily by local effects. 

The most well known commercial reservoir controlled release systems deliver hormones for contraception from hydrophobic polymers. The Norplant subcutaneous device controls the release of levonorgestrel with silicone rubber, and the Progestasert intrauterine device (lUD) releases progesterone from reservoir devices of ethylene vinyl acetate. In the field of insecticides, reservoir dispensers called BioLure were developed to provide zero-order release ofinsect pheromones to disrupt mating (Smith et al, 1983). The dispenser consists of a slab configuration with a rate-controlling membrane, with constant release described by Eq. 1. 

Menorrhagia also may be treated with the levonorgestrel-releasing intrauterine device (IUD). This is a very effective treatment that consistently reduces menstrual flow by 90% or greater.29,30 Its use has resulted in the postponement or cancellation of scheduled endometrial resection surgery or hysterectomy. Specifically, 60% of treated patients have been able to avoid hysterectomy.30,34,35... 

Mirena is a relatively new intrauterine contraceptive device that releases levonorgestrel into the uterine cavity for 5 years. Use of this contraceptive device is associated with fewer systemic progestin side effects and is at least as effective as Norplant. 

A systematic review of Mirena, an intrauterine progestogen release system (56), has attracted correspondence (57,58). Like other devices, Mirena releases levonorgestrel, in this case 20 micrograms/day. Since it had no greater efficacy than the Copper T device and was very much more costly, the debate has turned on safety. Amenorrhea is common with this device, as with others like it, and correspondents have pointed out that this is regarded by many women as an unwelcome complication. 

Li C-FI, Lee SSN, Pun TC. A pilot study on the acceptability of levonorgestrel-releasing intrauterine device by young, single, nulliparous Chinese females following surgical abortion. Contraception 2004 69 247-50. 

Gerber B, Reimer T, Krause A, Friese K, Muller H. Levonorgestrel-releasing intrauterine devices. Lancet 2001 357(9258) 801. 

Contraceptive devices, for example IUDs. These usually consist of a plastic T-shaped frame fitted with copper bands or wires. There are also intrauterine progesterone-only devices, which release levonorgestrel directly into the uterus. 

Robinson GE, Bounds W, Kubba AA, Adams J, GuiUeband J. Functional ovarian cysts associated with the levonorgestrel releasing intrauterine device. J Fam Plan 1989 14 131-2. 

Toivonen J, Luukkainen T, Allonen H. Protective effect of intrauterine release of levonorgestrel on pelvic infection three years comparative experience of levonorgestrel- and copper-releasing intrauterine devices. Obstet Gynecol 1991 77(2) 261. ... 

Intrauterine devices (IUDs) can also contain the steroids. One style contains 38 mg of progesterone, which is released slowly over 1 year. One containing levonorgestrel is under development. Unmedicated rings appear to work just as effectively, although the details of their action are not well known. They appear to create an environment unsuitable for sperm and ovum and inhibit implantation. They can be made of polyethylene, stainless steel, or copper, with the last being the most common. 

Suhonen SP, Allonen HO, Lahteenmaki P. Gynecology Sustained-release estradiol implants and a levonorgestrel-releasing intrauterine device in hormone replacement therapy. Am J Obstet Gynecol 1995 172 562-567. 

Copper or levonorgestrel-releasing intrauterine devices (lUD) and depot progestogen-only injections may be used as alternative eontra-eeptive methods, partieularly for women requiring hormonal eontraeep-... 

Fedele L, Bianchi S, Raffaelli R, Portuese A, Dorta M (1997) Treatment of adenomyosis-associated menorrhagia with a levonorgestrel-releasing intrauterine device. Fertil Steril 68 426-429... 

Mercorio F, De Simone R, Di Spiezio Sardo A, Cerrota G, Bifulco G, Vanacore F, Nappi C (2003) The effect of a levonorgestrel-releasing intrauterine device in the treatment of myoma-related menorrhagia. Contraception... 

Kelekci S, Kelekci KH, Yitmaz B. Effects of levonorgestrel-releasing intrauterine system and T380A intrauterine copper device on dysmenorrhea and days of bleeding in women with and without adenomyosis. Contraception 2012 86(5) 458-63. 

Intrauterine contraceptive devices (lUCDs) have been reviewed (1,2). Most are composed of bland synthetic materials or contain in addition a small amount of metallic copper. Others are designed to release either progesterone or a synthetic progestogen (for example levonorgestrel) (3,4). lUCDs that release levonorgestrel are somewhat more effective than copper-containing devices, while those that release progesterone are less effective (5). 

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