Rupture uterus in first and second trimester in a non-scarred uterus is generally seen with associated mullerian anomalies. A 22 year old primigravida with 16 weeks gestational age presented with pain in abdomen since 6 hours prior to admission and hypovolemic shock. Though she had taken regular antenatal visits and a transabdominal scan at 14-16wks with the report opining a normal study, the diagnosis of the fetus in the rudimentary horn was missed. A provisional diagnosis of rupture of right rudimentary horn of a bicornuate uterus was made afet clinical examination and the TVS showing the cervix continuing into a normal uterus with no fetus within it and a vague right adnexal mass. Transabdominal scan also showed vague hypoechoic mass in the right adnexa with a fetus of 16-17 weeks above the mass with absent cardiac activity. Emergency laparotomy with resuscitation and excision of the ruptured horn and blood transfusion saved the life of the patient.
