Pressure dynamics in the non-gravid uterus: Development of an intrauterine pressure threshold to confirm tubal occlusion after nonsurgical permanent contraception
Awarded 2015
Complex Family Planning Fellowship Research
Eva Patil , MD
Oregon Health and Science University

Our overarching goal is to simplify confirmation of tubal occlusion following hysteroscopic and nonsurgical permanent contraception. Hysteroscopic permanent contraception with the Essure® system has become an increasingly popular option for women and other approaches that require no surgery (nonsurgical permanent contraception (NSPC)) are a recent focus for contraceptive development. However, the verification test for tubal occlusion following these procedures also limits its accessibility. The current standard of care, hysterosalpingogram (HSG), is cumbersome, costly, requires a skilled professional and specialized equipment and typically cannot be done in an office setting. A ‘point of care’ test to confirm tubal occlusion that is simple and minimizes inconvenience or discomfort for the woman could help increase the acceptability of, access to and use of hysteroscopic and NSPC methods and facilitate the expansion of these approaches into low resource settings.
Data from the infertility literature demonstrates increased tubal pressures with blocked tubes but this has not yet been studied in women desiring highly effective permanent contraception. Obtaining intrauterine pressures can be performed using a small manometer attached to an intrauterine balloon catheter in the office, with minimal training of the provider and minimal discomfort to the woman. We believe that intrauterine pressures may be used for confirmation of tubal occlusion following NSPC
The first stage of our proposed project is a cross-sectional, descriptive pilot study of intrauterine pressures taken in 150 consenting women presenting for hysterosalpingogram (HSG) for any indication. This will allow us to measure intrauterine pressure in a wide variety of women and to compare pressures in women with patent and occluded fallopian tubes. Additionally, we will evaluate the extent to which other factors are associated with intrauterine pressures such as BMI, parity or menstrual cycle stage. We will then utilize this information to determine a threshold pressure for blocked tubes and then test the predictive value of this threshold for diagnosing fallopian tube occlusion as compared to a HSG, the current gold standard. The second stage will be a validation study in which the previously established pressure threshold will be compared against the HSG in a separate cohort of women. Future studies will apply these results to the development of a low-cost instrument for intrauterine pressure measurement. This tool could make confirmation of tubal occlusion after hysteroscopic and NSPC more accessible, affordable and patient-friendly thus increasing patient use of this safe and reliable form of contraception.
This project will yield novel information regarding intrauterine pressures in women with normal anatomy, abnormal anatomy, and following tubal occlusion procedures. Our hypothesis is that an intrauterine pressure threshold exists that will correctly identify women with tubal patency following an occlusion procedure with acceptable sensitivity and specificity. Development of a point-of-care test using this intrauterine pressure threshold would greatly reduce the number of women referred for HSG.