Single fetal demise in twin pregnancy

The management of a twin pregnancy in which one of the fetuses has died can be challenging and requires careful consideration of several factors.

Firstly, the etiology of the fetal demise should be investigated to determine if there are any ongoing risks to the surviving twin. Possible causes of fetal demise in a twin pregnancy include twin-twin transfusion syndrome, congenital anomalies, placental insufficiency, abnormal cord insertion, intrauterine infection, maternal medical conditions, intrauterine growth restriction, twin reversed arterial perfusion, foetal reduction, umbilical vein thrombosis, and complications following the death of a co-twin.

The chorionicity of the pregnancy should also be determined, as this can influence the risk of complications for the surviving twin. Monochorionic twin pregnancies are at higher risk for complications than dichorionic diamniotic twins, and require close monitoring with fetal ultrasound assessments every two weeks from 16 weeks of gestation onwards.

If the surviving twin is in a cephalic presentation and is not growth-restricted, vaginal delivery may be considered. However, if the live twin is malpresenting or growth-restricted, or if the dead twin is leading, caesarean section is preferred to reduce the risk of complications during delivery.

In cases where the fetal demise occurred in the first trimester, the remaining twin may be at lower risk for complications than if the demise occurred later in the pregnancy. However, regular non-stress tests should be undertaken to monitor the health of the surviving twin.

For patients undergoing assisted reproductive techniques, it is important to discuss the risks associated with multiple pregnancies and the possibility of fetal demise with their healthcare provider. Close monitoring and timely intervention can help to reduce the risk of complications for both the mother and the surviving twin.