To the Editor: In a recent article by Foran,1 information provided on the new Essure (Conceptus, Inc) permanent birth control or sterilisation method was inaccurate in several respects.

Firstly, Foran stated, incorrectly, that the Essure method is performed laparoscopically (it is actually a hysteroscopic method). This is a significant error, as one of the unique advantages of this method is the avoidance of incisional surgery, particularly laparoscopy and a general anaesthetic. This hysteroscopic procedure is well tolerated and can be performed with minimal or no sedation, followed by a rapid postprocedure recovery and early return to normal activity.2,3

Secondly, the failure rate in terms of postprocedure pregnancy is much less than the 0.6% quoted by Foran. To date, no pregnancies have been recorded in Phase II2 or Phase III3 multicentre, prospective, single-arm clinical trials conducted according to US Food and Drug Administration guidelines between 1998 and 2003. To date, no pregnancies have occurred in women relying on this intratubal microinsert during a combined 15 635 women-months of follow-up. The effectiveness rate for pregnancy prevention after 2 years of follow-up is 100% (95% CI, 99.5%–100%).

Thirdly, it is not a titanium insert. The metal used in the outer dynamic coil is a nickel–titanium alloy commonly known by the trade name Nitinol.

Fourthly, the adverse effects claimed (infection, bleeding) are misleading and incorrect. No infections within the uterus, tubes or pelvis have been recorded, and abnormal bleeding is not a feature of this form of sterilisation.2,3

Essure is the first hysteroscopic method of female sterilisation to gain regulatory approval for clinical use (in November 2002). This method of sterilisation offers women the choice of a less invasive, safe and reliable choice of sterilisation in the future.

In reply: Mea culpa! Essure is, of course, a hysteroscopic rather than a laparoscopic method of female sterilisation and is described so in the text of the article. I apologise for not picking up this error while checking the proofs. Kerin is also correct in pointing out that Essure is made not from pure titanium but from a titanium alloy. The possible adverse effects, though rare, are listed among a number of others in the manufacturer’s information brochure.1

I am always extremely wary of ascribing a 100% effectiveness rate to any contraceptive method. Since Essure has been used so far on only small numbers of women, the figure I quoted was the upper limit of the failure rate in world literature for female sterilisation procedures.2 Although initial experience indicates that the eventual success rate should be very close to 100%, Kerin’s quoted 95% CI suggests that, at present, we can only promise potential Essure users a better than 99.5% effectiveness rate (ie, a failure rate quite close to the figure I used).

I consider Essure to be an excellent new method of permanent contraception, and apologise if my article gave any other impression. I am certain that Australian women and their doctors will increasingly consider it an option in the future.