Blood specimen for neonatal thyroid screening is obtained at:

This is a controversial question Blood for neonatal thyroid screening is ideally obtained by heel prick between 2 and 4 days of life - placed on filter paper card & sent to central screening laboratory Cord blood may also be used, especially in regions where the neonates may not be brought for follow up after 48 hrs of life So, the best answer, among the given options is 72 hours after bih.