Levonorgestrel-releasing IUD as a method of contraception with therapeutic properties.Contraception. 1995 Nov; 52(5):269-76.C
The levonorgestrel-releasing intrauterine device LNg IUD is a new contraceptive method that combines the advantages of both hormonal and intrauterine contraception. It gives users non-contraceptive health benefits and can also be used as an effective therapy for menorrhagia. The local release of LNg within the endometrial cavity results in strong suppression of endometrial growth as the endometrium becomes insensitive to ovarian estradiol. The endometrial suppression is the reason for a significant reduction of menstrual blood loss or amenorrhea, and for the disappearance of dysmenorrhea. The bleeding pattern during the use of the LNg IUD is characterized by reduction of the blood loss and in the number of bleeding days per cycle. During the first two to three months of use, however, irregular spotting is common. The removal of the device results in a quick return of menstrual bleeding and fertility. The failure rate of copper-releasing IUDs, as with other methods of fertility regulation, is higher in young women and decreases with age. The LNg IUD, on the other hand, has the same low pregnancy rate in every age group of the users. The LNg IUD also gives protection against ectopic pregnancy and pelvic inflammatory disease and, by reducing menstrual blood loss, increases the body iron stores. The LNg IUD can be used to effectively treat menorrhagia. This has been demonstrated in studies with quantitative determination of menstrual blood loss. During the first year of use, the LNg IUD reduced menstrual blood loss by 90% from pretreatment levels. Comparative clinical trials with the LNg IUD cover more than 10,000 women-years of follow-up during use over five to seven years. The Pearl pregnancy rate in studies has been 0.0-0.2 per 100 women-years. The overall ectopic Pearl pregnancy rate is 0.02 per 100 woman-years. The LNg IUD is marketed in Denmark, Finland, Norway, Sweden and in the United Kingdom.