Twin Pregnancy Management

Definition and Clinical Significance

Twin pregnancies have approximately 5-fold increase in fetal death and 7-fold increase in neonatal death compared to singletons, primarily due to complications of prematurity 1

Determining chorionicity and amnionicity is essential in twin pregnancy management and should be established as early as possible 2, 3
First trimester ultrasound has nearly 100% accuracy in determining chorionicity, while accuracy decreases in later pregnancy 2

Women with twin pregnancies require more intensive monitoring than singleton pregnancies, including first trimester scan for dating and chorionicity determination 1
Women with twin pregnancies require more intensive monitoring than singleton pregnancies, including nuchal translucency scan at 11-14 weeks 1
Women with twin pregnancies require more intensive monitoring than singleton pregnancies, including detailed anatomic survey at 18-22 weeks 4
Women with twin pregnancies require more intensive monitoring than singleton pregnancies, including regular growth scans in the third trimester 1

Placenta previa is more common in twin pregnancies, especially dichorionic twins 5
Congenital anomalies are more common in twin pregnancies, particularly monozygotic twins (estimated to be 2-3 times greater than singletons) 5
Risk of major fetal anomaly affecting only one twin varies by chorionicity: 1 in 25 dichorionic twins, 1 in 15 monochorionic-diamniotic twins, and 1 in 6 monoamniotic twin pregnancies 7

Referral to a tertiary center may be appropriate for high-risk twin pregnancies, particularly monochorionic-monoamniotic twins 4, 8
The American College of Radiology recommends that monochorionic twins receive specialized care due to unique complications like twin-to-twin transfusion syndrome 1