At what age should newborn screening tests be conducted?

• A. At birth
• B. Between 1-24 hours
• C. Between 24-72 hours
• D. After 72 hours

Answer: (C)

Newborn screening tests are optimally conducted between 24 to 72 hours after birth. This timing is crucial because it allows for the identification of metabolic and genetic conditions that may not be evident immediately at birth. Many disorders detected through newborn screening have better outcomes when treated early, and certain conditions require a specific window following birth for accurate screening results.

Testing too early, such as right at birth or within the first 24 hours, could lead to false negatives or inaccuracies, as some metabolic processes may not yet be fully established in the newborn. Waiting until after 72 hours may delay crucial treatment and intervention, which is why the window of 24 to 72 hours is considered the most effective for obtaining reliable results. This period strikes a balance, ensuring that screening is conducted in time to initiate any necessary follow-up care.