A study (N Younge et al. NEJM 2017; 376: 617-28) provides some data on the slowly changing survival and neurodevelopmental outcomes among periviable infants (22-24 weeks gestation).
From epoch 1 (2000-2003), to epoch 3 (2008-2011), there has been some improvements. Overall survival increased from 30% to 36% and the percentage without neurodevelopmental impairment increased from 16% to 20%.
Mortality and Neurodevelopmental Outcomes at ~18 months of age (combined data and 11 centers)
The insightful commentary (pgs 694-6) notes that there has not been improvement in survival in infants born at 22 weeks. Furthermore, in reviewing multiple studies on outcomes, neurodevelopmental impairment was >94% in patients born at 22 weeks and between 80-90% for infants born at 23 weeks. At 24 weeks, neurodevelopmental impairment was present between 51-72%
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