The UK CRHRN has undertaken a number of studies looking at IUD use. The following is
some of the more recent work.
Cox, M.; Blacksell, S. Clinical performance of the Nova T380 IUD in routine
use by the UK Family Planning and Reproductive Health Research Network: 12 month report.
The Journal of Family Planning and Reproductive Health Care 2000 26(3)
Abstract: Doctors working in general practice and at family planning
clinics throughout the UK who collaborate in the UK Family Planning and Reproductive Health
Research Network were responsible for the fitting 572 Nova-T®380 intra-uterine contraceptive
devices (IUDs). The Nova-T® (and formerly the identical Novagard®) IUDs have copper with a
surface area of 200 mm2. The device used in this study, the Nova-T®380, has copper with a
surface area of 380 mm2. The purpose of the study was to evaluate the pregnancy and complication
rates of this new device, with its increased area of copper, in comparison with other published
results, in the clinical setting of British general practice and family planning clinics.
The 12-month cumulative life-table event rates were: pregnancy 0.8, expulsion 5.6, removal for
bleeding or bleeding and pain 11.0. The continuation rate was 73.4. The pregnancy rate at 12
months showed good contraceptive performance. The increased surface area of copper was not
associated with a reduced pregnancy rate, but as this was not a direct comparative study with
the Nova-T®, the influence of the increased area of copper must remain somewhat uncertain.
This study found the discontinuation rate for bleeding problems and pain with bleeding to be higher
than in other published studies. Other event rates were consistent with other published studies.
Cox M, Tripp J, Blacksell S. Clinical performance of the NOVA T®380 IUD in routine use
by the UK Family Planning and Reproductive Health Research Network*: Five-year report. The Journal
of Family Planning and Reproductive Health Care 200228(2).
Abstract:Objectives: The purpose of the study was to evaluate the pregnancy and
complication rates of this new device, with its increased area of copper, in comparison with other
published results, in the clinical setting of British general practice and family planning clinics.
Design:Doctors working in general practice and at family planning
clinics throughout the UK who collaborate in the UK Family Planning and Reproductive Health
Research Network were responsible for the fitting of 574 Nova T380® intrauterine contraceptive
devices (IUDs). The Nova T® (and formerly the identical Novagard®) IUDs have copper with a surface
area of 200 mm2. The Nova T380® has copper with a surface area of 380 mm2.
Results:This is the first 5-year report on this device. The 5-year
cumulative life-table event rates per 100 women were pregnancy 2.0, expulsion 13.0, and removal
for bleeding problems and bleeding with pain 29.6.
Conclusions:The increased surface area of copper was associated with
a reduced pregnancy rate as compared to the Nova T®, though no statistical comparison is possible.
Although the present study was not a direct comparative study with the Nova T®, the result lends
weight to the notion that increasing the copper reduces the pregnancy rate. The discontinuation
rate for bleeding problems and bleeding with pain and the expulsion rates were higher than in
published Nova T® studies.
Allison, CJ. Long-term use of the NovaT intrauterine device beyond five years compared
with routine refitting after five years of use: a multicentre study. British Journal of Family
Planning 1995 21(3)
Abstract:
In a multicentre study; the experience of 191 women wearing a Nova T IUD who decided to continue
long-term use of the device beyond the manufacturer’s recommended time limit of five years, was
compared with that of 141 Nova T users who at five years of use decided to opt for routine refitting
with another Nova T device. Gross cumulative event rates, calculated by the life-table method,
showed no significant difference between the events rates for the two groups during the subsequent
two years of use. The pregnancy and expulsion rate, and the rate for removal because of infection,
was low. The removal rate following complaints of bleeding and/or pain was low at 12 months and
moderate at 24 months of use. The larger sample of women in the long-term use group allowed
rates to be calculated at 36 months of use for this group. There was no rise in the pregnancy rate
during the third year of long-term use; a steep rise was shown in the rate of removal following
complaints of bleeding and/or pain, but it is possible that the reasons for this may not be directly
attributable to the Nova T.
An analysis of use-effectiveness data collected from an overlapping sample of 438 women fitted
with a Nova T IUD also showed use of the Nova T to be safe and effective method of
contraception.
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