Clinical outcomes and practical management implications in rudimentary horn pregnancies: a systematic review and pooled analysis (2010–2025)

PURPOSE: Rudimentary horn pregnancies are rare and carry significant maternal and fetal risks. This study aims to systematically review published cases of rudimentary horn pregnancies describing data about time of diagnosis, time of rupture, and live birth rate (LBR), with exploratory comparisons between communicating (CHP) and non-communicating horn pregnancies (NCHP). METHODS: A PRISMA-guided systematic search of PubMed, MEDLINE, and Cochrane (October 1, 2025) was performed with terms "unicornuate uterus pregnancy" OR "rudimentary horn pregnancy." Case reports, series, and reviews with defined clinical data were included; abstracts and unclear reports were excluded. Three independent reviewers extracted data using a standardized protocol. Descriptive statistics (means, medians, standard deviations, and ranges) and exploratory group comparisons (Fisher's exact test, Mann-Whitney U and Student's t test with p < 0.05 denoting significance) were performed. RESULTS: From 132 articles, 190 cases were included: 27 CHP (14.2%) and 163 NCHP (85.8%). Time of diagnosis was earlier in NCHP (15.9 ± 8.9 weeks) than CHP (22.1 ± 10.0 weeks, p = 0.01). Rupture occurred in 68 cases (35.8%), similarly in CHP (48.1%) and NCHP (33.7%, p = 0.19). Time of rupture was earlier in NCHP (18.7 ± 6.6 weeks) than CHP (23.0 ± 9.2 weeks, p = 0.02). Four cases attempted to continue pregnancy; all resulted in premature rupture. Reported live births were infrequent (11.6%) and more common in published CHP (25.9%) vs. NCHP cases (9.2%; p = 0.02). CONCLUSIONS: This descriptive synthesis indicates uterine horn communication may be associated with later diagnosis/rupture and reported live births were significantly more frequent in published CHP vs. NCHP cases. However, all comparisons are exploratory and must be interpreted with extreme caution, as data limitations preclude causal inference. Exhaustive imaging and diagnosis are essential to characterize horn type. Surgical termination is advised, but if expectant management is chosen, close monitoring and multidisciplinary care, including weekly ultrasounds, are advisable to mitigate complications.