| Popis: |
Levonorgestrel (LNG) has been recently introduced on the Danish market. In addition to being a contraceptive method, the LNG-releasing IUD also constitutes a therapeutic principle for idiopathic menorrhagia. The LNG-releasing IUD consists of a T-shaped plastic rod in which the vertical leg is surrounded by a cylinder that functions as a hormone reservoir and allows the release of LNG at a rate of 20 mcg/24 hours. The released hormone exerts in part a local atrophying effect on the endometrium and in part a slightly suppressing effect on the ovarian function. The preventive effect of this IUD is greater than that of the well-known copper IUD, and the risk of infection in connection with its use is significantly less. In contrast to the copper IUD, the LNG-releasing IUD reduces the amount and length of bleeding during menstruation, and only 20% of users experience amenorrhea. In Sweden and Finland LNG-releasing IUDs were compared in randomized studies to copper-T IUDs. LNG-releasing IUDs had a significantly lower Pearl index (0.1-0.6 vs. 3.3-6.7). In a multicenter study 937 women were randomized to Nova-T IUDs and 1821 women to LNG IUDs. Among LNG-releasing IUD users unwanted pregnancy occurred in 5 cases, equivalent to 0.5 per 100, and among Nova-T users 35 pregnancies occurred, corresponding to 5.9 per 100. In a Danish study with 1697 Nova-T IUD users the rate of pregnancy was even greater than 3.7/100 after 6 years of observation. In a 1994 Swedish study the rate (per 100 women) of expulsion during 5 years was 5.8 LNG and 6.7 Nova; bleeding problems 13.7 and 20.9 (p = 0.01), respectively; amenorrhea 6.0 and 0 (p = 0.001), respectively; hormonal side effects 12.1 and 2.0 (p = 0.001), respectively; and infection 0.8 and 2.2 (p = 0.01), respectively. The LNG-releasing IUD seems to be a new therapeutic method for menorrhagia. It is not yet clear whether this treatment principle can also be used for women with metrorrhagia. |
