Mirena Intrauterine System Timing of Insertion: A Randomized Controlled Trial

In order to determine the timing of LNG-IUS insertion that results in a greater proportion of
women using the LNG-IUS at 6-months post-partum, we will perform a randomized control trial
of interval versus immediate post-placenta insertion. Women will be enrolled at 36-weeks
gestation and greater. At the time of vaginal delivery, women will be randomized to receive
either immediate post-placenta insertion of the LNG-IUS or routine insertion at 4-8 weeks
post-partum. All patients will return at 4-6 weeks post-insertion and 6 months post-partum to
confirm correct position of the LNG-IUS. The primary outcome of this sub-study is the number
of LNG-IUS in the correct position at 6-months. Secondary outcomes include assessing the
safety of post-placental LNG-IUS insertion and difference in acceptability and symptoms
experienced by participants. This is a sub-study of the Contraceptive Choice Project, a
prospective cohort study that aims to improve the use of long-acting contraception by
removing financial barriers which has already enrolled over 5,000 patients. Association of
this study with CHOICE offers unique advantages including infrastructure to support subject
recruitment, retention and completion of follow-up as well as covering the cost of LNG-IUS
devices.

We hypothesize that, despite higher expulsion rates, women randomized to receive the LNG-IUS
immediately after placenta delivery will have higher rates of LNG-IUS continuation due to
poor rates of follow up in the interval insertion group. This is likely to be particularly
noticeable in our patient population, which is largely uninsured with poor access to
healthcare. Further, typical symptoms of LNG-IUS insertion include bleeding and cramping,
which may be disguised by the post-partum period. Published reports of immediate
post-placenta insertion focus on expulsion rates and do not report on symptoms and
satisfaction rates.