Hysteroscopic Methotrexate Injection Under Ultrasonographic Guidance for Interstitial Pregnancy

A 36-year-old woman presented with pelvic pain and vaginal blood loss and interstitial pregnancy (a single gestational sac located in the proximity of the right uterine horn, without visualization of an embryo and/or attachments inside) on 2- and 3-dimensional ultrasonographic examination. The patient was clinically stable. Her abdomen was soft with normal peristalsis; superficial and deep palpation were painless, as was decompression. With the patient under general anesthesia, an operative hysteroscopy was performed visually via ultrasound. A slow injection of methotrexate solution was pushed through the right cornual region inside the gestational sac and into the myometrial tissue tangentially at the 4 cardinal points. Twelve weeks later, the patient exhibited normal tubal patency via sonohysterography, as well as a viable pregnancy of 7 weeks' gestation. This minimally invasive approach is well tolerated and shows promise for the management of interstitial pregnancy, with no adverse effect on potential subsequent fertility.