Spontaneous twin pregnancy in uterus bicornis unicollis complicated with preeclampsia: A case report

INTRODUCTION AND IMPORTANCE: Bicornuate uterus is a uterine malformation caused by abnormal Müllerian fusion, often leading to multiple obstetric complications. A twin pregnancy in this condition is extremely rare. CASE PRESENTATION: A 27-year-old patient (Gravida 3, Para 0) with a previous history of two spontaneous early miscarriages was diagnosed with uterus bicornis unicollis (unicervical bicornuate uterus). She presented with spontaneous twin pregnancy complicated with preeclampsia at 34 weeks + 6 days. Thus, she underwent cesarean section with two separate lower-segment incisions. Consequently, healthy twins were delivered successfully. CLINICAL DISCUSSION: Bicornuate uterus is a rare congenital uterine malformation, and only 16 cases of twin pregnancy associated with uterus bicornis unicollis have been reported worldwide. This uterine malformation can be discovered spontaneously in imaging or during obstetric complications such as spontaneous abortions, premature labor, premature rupture of membranes, malpresentations, and intrauterine growth restriction. In addition, the risk for preeclampsia in twin pregnancies is twice higher than singleton gestations. CONCLUSION: Twin pregnancy in a bicornuate uterus is extremely rare; this phenomenon is yet to have guidelines for monitoring pregnancy and the mode of delivery.