complications occuring in the fetus or neonate

Last reviewed 04/2022

In twin pregancies there is an excess mortality and morbidity; monozygotic twins have a mortality nine times that of singletons, dizigotic three times.

Complications include:

  • congenital malformations - neural tube defects, heart abnormalities, incidences of Turner's and Klinefelter's syndromes are all increased. Overall, malformations occur twice as often in twin than in singleton pregnancies
  • twin to twin transfusion
  • preterm delivery and low birth weight, as discussed elsewhere
  • respiratory distress syndrome and infection