Twin gestations: monitoring of complications and anomalies with US.

An evaluation of 227 consecutive twin gestations was undertaken to assess the role of ultrasound (US) in the diagnosis of major obstetric complications and congenital anomalies. US accurately depicted the growth and development of fetuses in 65 patients with underlying maternal disorders that produced additional risks to the pregnancy. Complications such as malpresentations (104 cases), polyhydramnios (15 cases), oligohydramnios (five cases), and uterine myomas (seven of 11 cases) were demonstrated prenatally with US. Fetal anomalies included anencephaly (two cases), hydrocephalus (two cases), conjoined twins (three cases), twin-twin transfusion syndrome (five cases), and acardiac monsters (two cases). Demise of one twin in 20 gestations and demise of both twins in 18 gestations (overall mortality of 17%) were correctly identified with US. These 38 gestations included intrauterine demise in 12, spontaneous abortion in 13, and neonatal deaths in 13. Therefore, when multiple gestations are suspected clinically, serial real-time US scans should be obtained beginning in the first trimester.