Translating evidence into practice: new evidence about the risk of uterine perforation associated with IUD insertions in post-partum and breastfeeding women
Background on LARC: balancing the benefits with the risks
Long acting reversible contraception (LARC) provides highly effective contraception which has few contraindications, is highly acceptable and is associated with high rates of long term continuation. LARC have been shown to significantly reduce unintended pregnancy, teenage birth rates and abortion rates when promoted on a large scale. Intrauterine methods, either levonorgestrel (LNG-IUD) or copper-bearing (Cu-IUD), are suitable for a wide range of women including young nulliparous women and post-natal women. While IUDs are a very safe method of contraception women need to be aware of the small risk of complications, including insertion-related complications. These include a low risk of infection in the first 3 weeks after insertion, expulsion of the device, method failure and perforation of the uterus during sounding or device insertion.
Providing information about the risks as well as the benefits of all contraceptive methods in a way that is easy for women to understand is an important part of all contraception consultations. It is therefore essential that as clinicians we have access to the latest data and can put this into context for our patients.
A new study on IUDs: who is most at risk of uterine perforation?
A recently published study which followed a total of 61,448 women in six European countries who had either a LNG-IUD (70%) or Cu-IUD (30%) inserted between 2006 and 2013 specifically looked at perforation rates. The study, called the European Active Surveillance Study on Intrauterine Devices, was the first large scale prospective non-interventional study to look at this issue and it was powered to test whether the LNG-IUD was ‘non-inferior’ to the Cu-IUD in relation to perforation rates. The researchers used very robust methodology with the results from the 12-month post-insertion questionnaire being validated through medical records by treating physicians. The researchers were conservative in their definition of perforation and included all cases where the IUD crossed the endometrium and entered the myometrium (i.e. partial as well as complete perforations).
What did the study show?
Importantly and reassuringly the study confirmed that the risk of perforation with IUD insertion is very low and when it does occur it has a ‘benign course’ with none of the perforations leading to serious illness or injury.
Only 81 perforations were reported overall with similar rates for the LNG and copper devices:
LNG-IUDs: perforation rate 1.4/1000 insertions (95% CI 1.1 - 1.8)
Cu-IUDs: perforation rate 1.1/1000 insertions (95% CI 0.7 - 1.7)
The key finding of the study is that breastfeeding and time since delivery were independently associated with an increased risk of perforation:
Breastfeeding women have a relative risk (RR) of perforation of 6.1 (95% CI 3.9 - 9.6) compared to non-breastfeeding (with no difference between LNG-IUDs and Cu-IUDs)
Postnatal women who are 36 weeks or less since delivery have an increased risk of perforation compared to women more than 36 weeks since delivery:
In breastfeeding women rate was 5.6 vs 1.6/1000
In non-breastfeeding women rate was 1.7 vs 0.7/1000
Almost all of the 81 perforations were associated with known risk factors (including a slightly higher rate in less experienced inserters).
Implications for practice
This large study provides important information to support women in making an evidence-informed contraceptive choice. While the World Health Organisation and FSRH in the UK support the insertion of IUDs from 4 weeks after delivery in our Family Planning NSW practice we usually defer insertion to 8 or sometimes 12 weeks. All women who are currently postnatal and breastfeeding should be informed about the relatively higher perforation rate in this context and our consent form and IUD assessment form are currently being updated to reflect this important new data.
Women considering this effective LARC can be reassured that the risk of perforation is very low, including for women who are postnatal and breastfeeding, but some may choose to defer insertion (but should of course be provided with an effective alternative in the meantime!)
Read the research article here
