Rupture of a Nongravid Unicornuate Uterus Following Failed Induction of a Noncommunicating Rudimentary Horn Pregnancy: A Rare Case Report.

Pregnancy within a non-communicating rudimentary horn is a rare and potentially life-threatening form of ectopic gestation associated with Müllerian duct anomalies. Diagnosis is frequently delayed because ultrasonographic findings may mimic those of a normal intrauterine pregnancy. We report the case of a 24-year-old gravida 2 para 1 woman who presented with a 14-week-and-6-day missed abortion initially interpreted as intrauterine pregnancy. Medical induction with misoprostol failed to achieve cervical dilatation; a mechanical cervical ripening attempt with a transcervical Foley catheter also failed, and oxytocin infusion was subsequently started. Shortly afterward the patient developed severe abdominal pain with hemodynamic compromise. Emergency laparotomy demonstrated a right-sided non-communicating rudimentary horn pregnancy within a unicornuate uterus. The gravid rudimentary horn remained intact, while a full-thickness rupture was identified in the posterolateral wall of the nongravid unicornuate uterine cavity; direct intraoperative inspection confirmed this rupture to be iatrogenic, resulting from a false passage created during Foley catheter insertion and propagated by subsequent oxytocin-induced contractions. Excision of the rudimentary horn, together with the ipsilateral fallopian tube, and repair of the uterine rupture were successfully performed. Persistent failed induction in a presumed second-trimester missed abortion should prompt evaluation for obstructive Müllerian anomalies, including noncommunicating rudimentary horn pregnancy, before further mechanical instrumentation is attempted.