Hormonal intrauterine devices
Related Experiment Video
Updated: Nov 6, 2026

Methods for Studying Uterine Contributions to Pregnancy Establishment in an Ovariectomized Mouse Model
Published on: April 7, 2023
G Rybo1, K Andersson, V Odlind
1Department of Obstetrics and Gynecology, University of Göteborg, Ostra sjukhuset, Sweden.
Abstract:
Intrauterine administration of progestogens from an IUD was introduced more than 15 years ago in order to improve the contraceptive efficacy and to reduce side-effects. A device releasing 20 micrograms levonorgestrel daily (Levonova) with a life span of at least 5 years is now available and has been subjected to an extensive study including 1821 women followed during 5 years. The safety and efficacy were evaluated in comparison to Cu-T IUDs. The pregnancy rate (Pearl index) was 0.09. During the first two cycles after insertion intermenstrual bleeding was common, otherwise the frequency of side-effects was low. The results seem to justify the conclusion that intrauterine administration of progestogens represents a further development of IUDs and hormonal contraception. Furthermore, these devices have proven to be effective in treatment of heavy menstrual blood losses. In many menorrhagic women, use of these IUDs can replace more invasive surgical methods such as hysterectomy or endometrial resection. Intrauterine administration of progestogens is also effective in opposing the proliferative effect of oestrogen on the endometrium in women on hormonal replacement therapy.
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