Ipsilateral tubal ectopic pregnancy associated with a rudimentary horn in a unicornuate uterus: report of two cases and literature review

Ectopic pregnancy in a unicornuate uterus with a rudimentary horn is a uncommon Müllerian anomaly. Ipsilateral tubal pregnancy adjacent to the rudimentary horn is rarer still, with only sporadic reports. No international guidelines exist for its diagnosis or management, leaving clinicians without clear guidance on optimal treatment, particularly when fertility preservation is desired. Here we describe two cases of ipsilateral tubal pregnancy associated with a non-communicating rudimentary horn: a 35-year-old woman with a type II horn and acute hemorrhage who was successfully managed by emergency laparoscopic salpingectomy, and a 32-year-old woman with a type III horn who was treated conservatively with methotrexate and mifepristone, with rapid β-hCG decline. In both cases, three-dimensional transvaginal ultrasonography accurately identified the uterine anomaly and the gestational sac, enabling prompt intervention. These cases illustrate that advanced sonography should be routinely used when a unicornuate uterus is suspected; treatment should be tailored to clinical stability and β-hCG levels; and the decision to resect the rudimentary horn should balance the risk of future horn pregnancy against potential myometrial damage and uterine rupture. Our experience offers practical guidance for clinicians and highlights the need for larger prospective cohort studies to establish evidence-based protocols.