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Optimal treatment for women with a persisting pregnancy of unknown location, a randomized controlled trial: The
Kurt T Barnhart1, Mary D Sammel2, Mary Stephenson3
1Department of Obstetrics and Gynecology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, United States; Department of Biostatistics and Epidemiology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, United States.
Objective:
Pregnancy of unknown location (PUL) is not a diagnosis but a transient state used to classify a woman when she has a positive pregnancy test without definitive evidence of an intra-uterine or extra-uterine pregnancy on transvaginal ultrasonography. Management of a persisting PUL varies substantially, including expectant or active management. Active management can include uterine cavity evacuation or systemic administration of methotrexate. To date, no consensus has been reached on whether either management strategy is superior or non-inferior to the other.
Design:
Randomized controlled trial.
Setting:
Academic medical centers.
Patients:
We plan to randomize 276 persisting PUL-diagnosed women who are 18 years or older from Reproductive Medicine Network clinics and additional interested sites, all patients will be followed for 2 years for fertility and patient satisfaction outcomes.
Interventions:
Randomization will be 1:1:1 ratio between expectant management, uterine evacuation and empiric use of methotrexate. After randomization to initial management plan, all patients will be followed by their clinicians until resolution of the PUL. The clinician will determine whether there is a change in management, based on clinical symptoms, and/or serial human chorionic gonadotropin (hCG) concentrations and/or additional ultrasonography.
Main Outcome:
The primary outcome measure in each of the 3 treatment arms is the uneventful clinical resolution of a persistent PUL without change from the initial management strategy. Secondary outcome measures include: number of ruptured ectopic pregnancies, number and type of re-interventions (additional methotrexate injections or surgical procedures), treatment complications, adverse events, number of visits, time to resolution, patient satisfaction, and future fertility.
Conclusion:
This multicenter randomized controlled trial will provide guidance for evidence-based management for women who have persisting pregnancy of unknown location.
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