What are the two methods used to estimate gestational age?

The correct choice focuses on the Dubowitz and New Ballard Score as methods to estimate gestational age in newborns. These scoring systems involve a physical and neurological examination of the infant, assessing various criteria such as skin texture, presence of lanugo, and development of the genitalia. The findings are then combined to provide an estimate of gestational age.

The Dubowitz score is one of the earliest scoring systems developed for this purpose, while the New Ballard Score is a revised version that improves upon the original by offering a more comprehensive assessment. These tools are particularly useful in clinical settings where determining the gestational age is crucial for proper medical management and intervention for preterm or ill infants.

Other options mention methods that are not primarily designed for estimating gestational age. For example, the Apgar score is used to evaluate a newborn's condition immediately after birth, focusing on factors such as heart rate, respiratory effort, muscle tone, reflex response, and skin color, rather than estimating gestational age. Weight and length measurements may provide some information about an infant's growth status but are not reliable methods for accurately determining gestational age.