The TCu380 Slimline or TCu380A: a systematic review of comparative data
Westside Contraceptive Services, London, UK
Objectives: TCu380S (GyneT Slimline) is an IUD very similar to TCu380A
but has been modified so that the copper collars are seated flush on the
horizontal crossbar of the device. This is intended to facilitate manufacture,
loading and insertion of the device. Despite its popularity, the device has been
withdrawn from many markets. This review examined the evidence comparing the
Slimline version to the standard TCu380A.
Design and methods: Medline and the Cochrane Library were searched for
randomised trials comparing TCu380S to the standard TCu380A, and the articles
retrieved. Trials were assessed for threats to validity. Data was combined using
the general variance based method where studies are weighted to the inverse of
Results: Two trials in three reports, involving 11,564 women, were
included which compared TCu380S to TCu380A. After the first year the pregnancy
rate tended to be lower with the Slimline version, though not significantly (rate
ratio 0.22 95% CI 0.24 to 1.18, one trial, at the end of the fifth year). The
absolute difference was around 1% in the later years. The expulsion rate was
higher at one year with TCu380S (rate ratio 1.73, 95% CI 1.17 to 2.55, two
trials), but this tended to decline, and at 5 year the cumulative rate though
still higher, was not statistically so (rate ratio 1.25, 0.83 to 1.89, one
trial). There was no difference in removals for bleeding and/or pain at any
interval (rate ratio 1.03, 0.75 to 1.43 at one year, two trials).
Conclusions: The TCu380S is a popular version of the worldwide
standard, TCu380A, because of the ease of loading the device. If the Slimline
device is easier to insert, this is not reflected in reduced expulsion rates.
Any excess in expulsions in the trials in this review was not associated with a
higher pregnancy rate. Greater efforts should be made to reinstate this popular
device where it has been withdrawn.