Pregnancy in Non-Communicating Unicornuate Uterus: Diagnosis Difficulty and Outcomes – a Case Report

Abstract

Approximately 1 in every 76,000 pregnancies develops within a unicornuate uterus with a rudimentary horn. Müllerian uterus anomalies are often asymptomatic, thus, the diagnosis is a challenge, and it is usually made during the gestation or due to its complications, such as uterine rupture, pregnancy-induced hypertension, antepartum, postpartum bleeding and intrauterine growth restriction (IUGR). In order to avoid unnecessary cesarean sections and the risks they involve, the physicians should consider the several approaches and for how long it is feasible to perform labor induction in suspected cases of pregnancy in a unicornuate uterus with a rudimentary horn, despite the rarity of the anomaly. This report describes a case of a unicornuate uterus in which a pregnancy developed in the non-communicating rudimentary horn and the consequences of the delayed diagnosis. Palavras-chave ResumoAproximadamente 1 em cada 76 mil gestações se desenvolvem em útero unicorno sem comunicação com o colo uterino. Anomalias müllerianas uterinas são, na maioria das vezes, assintomáticas, tornando difícil o diagnóstico, que geralmente é esclarecido durante a gestação ou por conta das complicações gestacionais, como ruptura uterina, hipertensão gestacional, parto pré-termo, hemorragias pós-parto e crescimento intrauterino restrito (CIUR). Com o intuito de evitar cesáreas desnecessárias e os riscos que esse procedimento envolve, considerações devem ser feitas quanto aos diferentes métodos utilizados, e por quanto tempo é viável induzir o parto na possibilidade de útero não comunicante, mesmo sendo uma anomalia rara. Este relato descreve um caso de uma gestação que se desenvolveu em um útero unicorno não comunicante com o colo uterino e as consequências do diagnóstico tardio.

Successful management of a rudimentary uterine horn ectopic pregnancy by combining methotrexate and surgery: A case report

“…The wide reported range of the incidence of rudimentary horn pregnancies (1 per 76 0000 to 1 per 150 0000 pregnancies) [1,[3], [4], [5], [6],9,[11], [12], [13],18] reflects the rarity of the condition. A decrease in the mortality rate from 23% to 0.5% [2,11] in recent years may indicate that advances in imaging technology have allowed more accurate diagnosis of uterine malformations prior to pregnancy or before serious pregnancy-related complications arise [1,4].…”

“…The prevalence of rudimentary horn pregnancy is very low (1 in 76 000–150 000 pregnancies) [1,[3], [4], [5], [6],9,12,13,18]. It mainly occurs in a non-communicating rudimentary horn by transperitoneal migration of sperm or fertilized ovum [[3], [4], [5], [6],9,11,12]. The maternal and foetal prognosis in unrecognized rudimentary horn ectopic pregnancy is poor, with an average neonatal survival rate of 6% [11,15] and rate of uterine rupture close to 80% [1,2,4,5,11,15].…”

Timely Identification of Pregnancy in Noncommunicating Horn of Unicornuate Uterus by Three-Dimensional Transvaginal Ultrasonography

“…[ 6 ] A 3D ultrasound and/or magnetic resonance imaging (MRI) is advised if IUGR is observed with no risk factors and if uterine anomalies are suspected in an ultrasound examination in early pregnancy. [ 7 ]…”

“…The growing pregnancy in a rudimentary horn tends to displace the normal uterus giving a false picture of no uterine anomaly, which can only be detected by a 3D ultrasound examination or MRI. [ 7 ] Besides, 3D USG offers better patient tolerability. Although MRI is an excellent way of evaluating uterine anomalies, the drawback is that the procedure is expensive, time-consuming, and not widely available.…”

“…By diagnosing the anomaly in early pregnancy, it is possible to prevent complications such as uterine rupture, unnecessary induction of labor, and fetal death at a later gestation. [ 7 ]…”