Efficacy of transvaginal ultrasound-guided local injections of absolute ethanol for ectopic pregnancies with intrauterine implantation sites

BACKGROUND: Cervical pregnancies, interstitial tubal pregnancies, and cesarean scar pregnancies, which are ectopic pregnancies with intrauterine implantation sites exhibit increasing trends with the recent widespread use of assisted reproductive technologies and increased rate of cesarean deliveries. The development of high-sensitivity human chorionic gonadotropin testing reagents and the increased precision of transvaginal ultrasonic tomography have made early diagnosis possible and have enabled treatment. Removal of ectopic pregnancies using methotrexate therapy and/or uterine artery embolization has been reported. However, delayed resumption of infertility treatments after methotrexate therapy is indicated, and negative effects on the next pregnancy after uterine artery embolization have been reported. AIM: To examine the efficacy and safety of ultrasound-guided topical absolute ethanol injection in ectopic pregnancies with an intrauterine implantation site. METHODS: In this study, we retrospectively examined the medical records of 21 patients who were diagnosed with an ectopic pregnancy with an intrauterine implantation site at our hospital, between April 2010 and December 2018, and underwent transvaginal ultrasound-guided local injections of absolute ethanol to determine the treatment outcomes. We evaluated the treatment methods, treatment outcomes, presence of bleeding requiring hemostasis measures and blood transfusion, complications, and treatment periods. Successful treatment was defined as the completion of treatment using transvaginal ultrasound-guided local injections of absolute ethanol alone. RESULTS: There were 21 total cases comprising 10 cervical pregnancies, 10 interstitial tubal pregnancies, and 1 cesarean scar pregnancy. All patients completed treatment with this method. No massive hemorrhaging or serious adverse reactions were observed during treatment. The mean gestation ages at the time of diagnosis were 5.9 wk (SD, ± 0.9 wk) for cervical and 6.9 wk (SD, ± 2.1 wk) for interstitial tubal pregnancies. The total ethanol doses were 4.8 mL (SD, ± 2.2 mL) for cervical pregnancies and 3.3 mL (SD, ± 2.2 mL) for interstitial pregnancies. The treatment period was 28.5 days (SD, ± 11.7 d) for cervical pregnancies and 30.0 ± 8.1 d for interstitial pregnancies. Positive correlations were observed between the blood β- human chorionic gonadotropin level at the beginning of treatment and the total ethanol dose (r = 0.75; P = 0.00008), as well as between the total ethanol dose and treatment period (r = 0.48; P = 0.026). CONCLUSION: Transvaginal ultrasound-guided local injections of absolute ethanol could become a new option for intrauterine ectopic pregnancies when fertility preservation is desired.