Levonorgestrel-releasing (20 microgram/day) intrauterine systems (Mirena) compared with other methods of reversible contraceptives.

Abstract

OBJECTIVE:

To assess the relative contraceptive effectiveness, tolerability and acceptability of the levonorgestrel-releasing (20 microg per day) intrauterine system (LNG-20) compared with reversible contraceptive methods in women of reproductive age.

DESIGN:

A systematic review and meta-analysis of randomised controlled trials.

IDENTIFICATION:

Studies were identified through seven databases, and by contacting investigators and organisations working in the contraceptive field.

MAIN OUTCOME MEASURES:

Unplanned pregnancy and continuation of contraceptive method.

RESULTS:

Five of the seven randomised controlled trials which met the inclusion criteria were included in the meta-analyses; four were comparisons of the LNG-20 intrauterine system with nonhormonal intrauterine devices. LNG-20 intrauterine systems were compared with intrauterine devices divided into two categories, those > 250 mm3 (Copper T 380 Ag and Copper T 380A intrauterine devices) and those < or = 250 mm3 (Nova-T, Copper T 220C and Copper 200 intrauterine devices). Pregnancy rates for the LNG-20 intrauterine system users were significantly less likely to become pregnant compared with users of intrauterine devices < or = 250 mm3, and significantly less likely to have an ectopic pregnancy. LNG-20 intrauterine system users were more likely to experience amenorrhoea and device expulsion than women using intrauterine devices > 250 mm3. LNG-20 intrauterine system users were significantly more likely than all the intrauterine device users to discontinue because of hormonal side effects and amenorrhoea. When the LNG-20 intrauterine system was compared with Norplant-2, the LNG-20 users were significantly more likely to experience oligo-amenorrhoea, but significantly less likely to experience prolonged bleeding and spotting.

CONCLUSIONS:

The effectiveness of the LNG-20 intrauterine system was similar to or better than other contraceptive methods with which it was compared. Amenorrhoea was the main reason for the discontinuation of the LNG-20 intrauterine system, usually unnecessarily, since this end-organ suppression of bleeding is benign, associated with normal oestrogen levels. Women choosing this method should be informed of potential amenorrhoea when having pre-contraceptive counselling and that absent bleeding may be viewed as a positive outcome.

• Authors: R S French, F M Cowan, D Mansour, J P Higgins, A Robinson, T Procter, S Morris, J Guillebaud
• Journal: BJOG : an international journal of obstetrics and gynaecology (BJOG) Vol. 107 Issue 10 Pg. 1218-25 (Oct 2000) ISSN: 1470-0328 [Print] England
• PMID: 11028571 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't, Review, Systematic Review)

Chemical References

• Contraceptive Agents, Female
• Levonorgestrel

Topics

• Contraception (methods)
• Contraceptive Agents, Female (administration & dosage, adverse effects)
• Counseling
• Female
• Humans
• Intrauterine Devices, Medicated
• Levonorgestrel (administration & dosage, adverse effects)
• Menstruation Disturbances (chemically induced)
• Meta-Analysis as Topic
• Randomized Controlled Trials as Topic
• Risk Factors