When is growth hormone replacement therapy most successful?

• A. Immediately after birth
• B. Only during adolescence
• C. As soon as growth delays are noted
• D. At age 5

Answer: (C)

Starting growth hormone replacement as soon as a growth delay is detected yields the best response because there is more time for catch-up growth while the growth plates are still open. The earlier you intervene, the greater the potential for increasing height before puberty and before epiphyseal fusion limits further growth. Delaying therapy into adolescence or later reduces the available growth window and typically results in less gain in final height. Beginning therapy immediately after birth isn’t ideal for most cases because not every infant with low growth requires GH, and diagnosis needs to be confirmed along with ongoing growth monitoring. Starting at age five is later in the growth period, so it doesn’t optimize the height outcome compared with initiating at the first sign of growth delay.