Introduction

Prevalence of unicornuate uterus is 0.1% in the population, with 74% of unicornuate uterus having a rudimentary horn, which is present due to partial development of one mullerian duct. Rudimentary horn can be communicating or non-communicating depending on their fusion with the larger horn. When rudimentary horn fuses, it has a communication with the larger uterine horn, and when fusion fails, there is no communication between the rudimentary horn and the larger horn, with 70-90% of the times, rudimentary horn not communicating with the main horn [1]. Mullerian anomalies lead to multiple problems like infertility, endometriosis, dysmenorrhoea, recurrent mis-carriages, preterm birth, fetal growth restriction, placental abnormalities, increase caesarean section rates which affect morbidity and mortality of women[2][1][3]. Sometimes, unicornuate uterus has been associated with other malformations like musculoskeletal malformations, auditory defects, Hirschprung disease, absent gall bladder [2] and VACTERL anomalies [4].
Diagnosing uterine anomalies early, if possible during adolescents , and later during early pregnancy period will help to reduce morbidity and mortality with uterine rupture being as high as 80% [5], most uterine horn rupture occurring at 10-15 weeks of gestation [6][7]. There has been reports of pregnancy in rudimentary horn up till term, live [8, 9] and with fetal demise [3] but such conditions are extremely rare and should be avoided. If the clinician has an ectopic mind, and is suspicious that he’s dealing with ectopic pregnancy, he should keep in mind that he may be dealing with a uterine anomaly, else diagnosis may be missed. Detecting it is of utmost importance, because if not detected in time, pregnancy will progress to a stage where rupture is inevitable, and this will be detrimental for the woman.
We present a case where we detected pregnancy in the rudimentary horn of unicornuate uterus early by 3D vaginal ultrasound. Treatment was primarily surgical with laparoscopy being the mode of surgery.