EP21.19: Large myometrial defect after intragestational injection of methotrexate for Caesarean scar ectopic pregnancy

We report a case of a large myometrial dehiscence observed after local methotrexate (MTX) for a Caesarean scar ectopic pregnancy (CSEP). A 36-year-old G1P1 woman with a history of previous Caesarean section was referred to our tertiary referral centre for suspected CSEP (7 weeks of amenorrhea). She presented light vaginal bleeding. The β-hCG level was 63,237 mIU/mL. An endogenous, type I CSEP was diagnosed by transvaginal ultrasound (TVUS), contained an embryo with a Crown–rump length of 11.6mm and observable cardiac activity. The patient was treated with MTX, injected into the gestational sac under ultrasound guidance. The β-hCG level decreased through the following weeks being negative 8 weeks after the treatment. During the outpatient follow-up, performed in the institution from which she was initially referred to our centre, no complications were reported. Ten months later, the patient was sent back for re-evaluation in our Gynecological Ultrasound Unit. TVUS showed a severe dehiscence of the Caesarean scar, 25 x 38 x 43 mm, containing amorphous material (see figure 1). The patient underwent laparoscopic repair of this defect. More research data are needed to elucidate the risk factors for the complication described here, as well as to establish monitoring protocols that promote patient safety by allowing timely detection and correction of myometrial defects after conservative (pharmacologic) treatment of CSEP. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.