Survivability correlates with gestational age in infants who are appropriately grown. Babies born in singleton preganancies are more likely to survive than babies from multiple pregnancies.

50% of babies born at 24 weeks of gestation survive the neonatal period.

70% of babies born at 25 and 90% of babies born at 27 – 28 weeks survive the neonatal period

Neonatal mortality rate improves rapidly with each extra gestational week achieved at delivery. Neonatal mortality rate at 33 weeks is very low comparable to low mortality rate of babies born at term.