Editor—The levonorgestrel intrauterine system (Mirena), a useful addition to contraceptive choice, is now approaching its third anniversary.
In the United Kingdom the product licence for the levonorgestrel intrauterine system permits its use for three years. In all other countries where the system is marketed, however, its use is approved for five years. There is good evidence to support this longer duration,1 and indeed the system seems to remain effective for as long as seven years.2 We understand that Schering Healthcare has applied for a two year extension to its current licence, backed by their new data that relates to the new polymer that has been used since 1990.
Many clinicians have asked us if they should conform strictly to the current product licence and replace each intrauterine system on the third anniversary of its insertion. We would strongly advise delaying reinsertion in this time, at least until the expected statement from the Medicines Control Agency.
It is well known that the process of insertion of all intrauterine contraceptives causes problems (short term inconvenience and discomfort followed by new bleeding and pain or expulsion) and also real risks,3,4 notably perforation and upper genital tract infection. These would be unacceptable if it emerges that reinsertions were not necessary.
Users of the levonorgestrel intrauterine system can be reassured that good data are available to support its use for five years. From 15 May, and until any statement concerning a change in the licence, continuation beyond three years is legitimate, at the woman’s choice, provided the established criteria for use by named patients are observed—that is, explaining that this is unlicensed use of a licensed product; highlighting the risks and benefits of the proposed non-intervention; obtaining and recording the woman’s verbal consent in her case notes; and keeping a separate record of the woman’s name and the nature of the unlicensed use.5
Footnotes
Conflict of interest: The Margaret Pyke Memorial Trust is in receipt of research funds from Leiras and from Schering for three ongoing studies of Mirena, and has received research or educational grants from the previous franchisee, Pharmacia and Upjohn. DM and JG received ad hoc consultancy and lecture fees and associated expenses from these and other unrelated pharmaceutical companies.
References
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