Birth order and morbidity and mortality to hospital discharge among inborn very low-birthweight, very preterm twin infants admitted to neonatal intensive care: a retrospective cohort study.

In modern perinatology, second twins are still more unstable immediately after birth and require more resuscitation. After admission to the neonatal intensive care unit, they are at increased risk of RDS, but not other conditions, except for second twins delivered by C-section after a first twin delivered vaginally, who have decreased overall survival and survival without major brain injury.