Newborn screening shall be performed after how many hours of life and not later than how many days?

Newborn screening shall be performed after how many hours of life and not later than how many days?

• A. 12 hours, 2 days
• B. 24 hours, 3 days
• C. 36 hours, 4 days
• D. 48 hours, 5 days

Answer: (B)

Newborn screening relies on collecting a sample at a time when the markers it looks for are reliably detectable, yet early enough to allow prompt intervention if a disorder is found. The standard window is after 24 hours of life and within the first 3 days (no later than 72 hours). Waiting less than 24 hours can yield false negatives because some metabolic markers haven’t reached detectable levels yet, while delaying beyond 3 days can postpone treatment and worsen outcomes.

Newborn screening relies on collecting a sample at a time when the markers it looks for are reliably detectable, yet early enough to allow prompt intervention if a disorder is found. The standard window is after 24 hours of life and within the first 3 days (no later than 72 hours). Waiting less than 24 hours can yield false negatives because some metabolic markers haven’t reached detectable levels yet, while delaying beyond 3 days can postpone treatment and worsen outcomes.