Intrauterine contraception: incidence and factors associated with uterine perforation--a population-based study

Abstract

What are the incidence and factors associated with uterine perforation by modern copper intrauterine device (Cu-IUD) and the levonorgestrel-releasing intrauterine system (LNG-IUS)? Perforation incidence was similar to that reported in prior studies and did not vary between Cu-IUD and LNG-IUS groups. Lactation, amenorrhoea and a post-partum period of n = 17) and the LNG-IUS (n = 51) were analysed as one group and also compared using Mann–Whitney and chi-square tests. IUD/IUS sales numbers were used to calculate incidences. The overall incidence of perforation was 0.4/1000 sold devices, varying annually from 0 to 1.2/1000. The proportion of both sold and perforating LNG-IUSs increased during the study period, but perforation incidence was not affected. Demographic characteristics in the Cu-IUD and LNG-IUS groups were similar. More than half of the devices (55%) were inserted at <6 months post-partum. Breastfeeding at the time of insertion was common, comprising 32% of all patients. Moreover, of the breastfeeding women, 90% had delivered within 6 month prior to insertion. The population-based study setting represents a good overview of patients experiencing uterine perforation with an IUD/IUS. As previously reported, the post-partum period, lactation and amenorrhoea may increase the risk of perforation. As the study setting revealed only symptomatic patients or those attending regular follow-up, the true incidence might be somewhat higher. As there is no specific diagnostic code for uterine perforation or treatment, it is unlikely that all cases of uterine perforation can be identified in a retrospective study. Helsinki University Central Hospital research funds are acknowledged.