Midtrimester transvaginal ultrasound cervical length screening for spontaneous preterm birth in diamniotic twin pregnancies according to chorionicity

Monochorionic diamniotic twin pregnancies had a higher rate of spontaneous preterm birth than dichorionic diamniotic pregnancies. The higher rate of spontaneous preterm delivery in monochorionic pregnancies is associated with lower midtrimester TVU CL when compared to dichorionic pregnancies.