not). Mirena, besides not being any more effective in preventingintra or extrauterine pregnancies when compared with any of thestandard intrauterine systems containing more than 250mm3 ofcopper (copper T 380 Ag and copper T 380A)2, is also 11 timesmore expensive (£99 vs £9). There is in addition good evidence toshow that the short, medium and long term patient dissatisfactionrate for Mirena, assessed by discontinuation as a result of systema-tic androgenic side effects, menstrual irregularities and expulsionare higher than with users of intrauterine systems with more than250mm3 of copper3. The amenorrhoea produced by Mirena is notalways a positive side effect as some women view regularmenstruation as a sign of femininity which reassures them thatthey are neither pregnant nor menopausal.

The intrauterine contraceptive device for women withoutmenstrual problems should be standard copper T 380A and CopperT 380Ag, and not Mirena. If Mirena is to achieve its desired statusas the intrauterine contraceptive system of choice it needs tocompete in terms of cost, duration of contraceptive ef®cacy andincreased tolerability.

References

1. French RS, Cowan FM, Maansour D, et al. Levonorgestrel-releasing

(20ug/day) intrauterine systems (Mirena) compared with other methods

of reversible contraceptives. Br J Obstet Gynaecol 2000;107:1218±

1225.

2. Nilsson CG, Allonen H, Diaz J, Luukkainen T. Two years experience

with Levonorgestrel-releasing intrauterine devices and one copper-

releasing intrauterine device: a randomised comparative performance

study. Fertil Steril 1983;39:187±192.

3. Sivin I, Stern J. Health during prolonged use of levonorgestrel 20 micro-

grams/d and the copper TCu 380 Ag intrauterine contraceptive devices:

a multicenter study. International Committee for Contraceptive

Research (ICCR). Fertil Steril 1994;61:70±77.

B. A. OnyekaBlackpool Victoria Hospital NHS Trust, Blackpool, UK

PII: S0306-5456(00)00157-1

Authorsuthors' Replyeply

Sir,The aim of our systematic review was to investigate the contra-

ceptive properties of Mirena. Our review of the literature to July1998 showed no advantage of the Mirena intrauterine systemcompared with Copper T380 devices bearing copper bands ontheir side arms in terms of effectiveness and continuation rates.Moreover the latter are cheaper than the Mirena intrauterinesystems (the December 2000 `MIMS' price of the newly marketedT-Safe 380A which replaces the Gyne T 380S withdrawn forpurely commercial reasons in 1999 is £9.40, compared to £89.25for the Mirena and can be used for at least eight years.

A systematic review conducted by Lethaby et al. has investi-gated the evidence for the use of levonorgestrel-releasing systemsfor heavy menstrual bleeding1. Current evidence suggests that theMirena intrauterine system is effective and acceptable in the treat-ment of heavy menstrual bleeding. Using data derived from therandomised trial of Andersson et al.2, Suvisaari and Lahteenmaki3

demonstrated that, with the passage of suf®cient time since inser-tion, the initial mean increase in the duration of bleeding and

spotting actually reduces to less than the control populationusing a copper device.

The 60 month termination rates for oligo-amenorrhea (afrequent occurrence which signi®es no pathology) in the multi-centre study of Andersson et al.2 aried from 1.7% in Sweden to19.6% in Hungary (personal communication, I. Rauramo). Thismay suggest that the providers' attitudes (reassuring or otherwise)to users' reports of amenorrhea associated with the Mirena intrau-terine system in¯uence continuation of the method. Moreover arecent nation-wide post-marketing study by Backman et al.4 of17,914 Finnish women demonstrated that occasional or totallymissed menstruation was statistically associated with prolongedor continued use of the method (odds ratio 0.46, CI 0.43-0.5).

Maintaining women's choice and autonomy makes it essential inadvising women concerning intrauterine contraception.

References

1. Lethaby AE, Cooke I, Rees M. Progesterone/progestogen releasing

intrauterine systems versus either placebo or any medication for heavy

menstrual bleeding (Cochrane Review). The Cochrance Library. Issue

4. Oxford: Update Software, 2000.

2. Andersson K, Odlind V, Rybo G. Levonorgestrel-releasing and copper-

releasing (Nova T) intrauterine devices during ®ve years of use: a rando-

mised comparative trial. Contraception 1994;49:56±72.

3. Suvisaari J, Lahteenmaki P. Detailed Analysis of Menstrual Bleeding

Patterns After Postmenstrual and Postabortal Insertion of a Copper IUD

or a Levonorgestrel-Releasing Intrauterine System. Contraception

1996;54:201±208.

4. Backman T, Huhtala S, Blom T, Luoto R, Rauromo I, Koskenvuo M.

Length of use and symptoms associated with premature removal of the

levonorgestrel intrauterine system: a nation-wide study of 17,360 users.

Br J Obstet Gynaecol 2000;107:335±339.

Rebecca French, Diana Mansour, Angela Robinson &John GuillebaudDepartment of Sexually Transmitted Diseases, Royal Free andUniversity College Medical School, University College, London,UK

PII: S0306-5456(00)00158-3

Does histological incomplete excision of cervicalintraepithelial neoplasia following large excision oftransformation zone increase recurrence rates? A sixyear cytological follow up

Sir,I read this article with interest and the authors are to be congra-

tulated on their study. It clearly con®rms that women with incom-pletely excised CIN following large loop excision of thetransformation zone are at higher risk of recurrence. As with somany useful observations, it often asks new questions.

The ®rst of these concerns follow up. The authors conclude thatlong term colposcopic and cytological follow up are necessary.Why? The need for cytological follow-up is obvious, but what isthe evidence that colposcopy would improve pick-up rates? Thereare no data provided to suggest that colposcopy would addanything and would justify the increased costs and service pres-sures that would ensue. Colposcopy is said to be compromised inpreviously treated patients. No evidence is presented in this study

CORRESPONDENCE 771