Behavior of Macrosomic and Appropriate-for-Gestational-Age Newborns


Address for correspondence: Jana L. Pressler, RN, PhD, Assistant Professor of Nursing, Vanderbilt University, School of Nursing, Nashville, TN 37240.


Objective: To compare the behavior of macrosomic newborns who were vaginally delivered of healthy mothers without diabetes with that of non-macrosomic, appropriate-for-gestational-age (AGA) newborns.


Newborns were recruited conveniently from a tertiary hospital. Newborns were examined at 12–24 and 36–48 hours of age, using the Brazelton Neonatal Behavioral Assessment Scale (NBAS).


Thirty macrosomic newborns who were delivered vaginally were matched with AGA newborns for ethnicity, maternal education, parity, and obstetric medications.

Main Outcome Measures:

Dimensions scores derived from the individual NBAS items measured reflex functioning, response decrement, orientation, motor processes, range of state, autonomic stability, and regulation of state.


Macrosomic newborns performed weaker than AGA newborns on the reflex and motor dimensions. Both groups displayed improved motor scores on Day 2, but regulation of state scores were weaker. For orientation, AGA newborns scored higher on Day 1, and macrosomic newborns scored higher on Day 2.

Conclusions: Increased head, limb, and body mass of macrosomic newborns, compared with adjacent and overall muscle strength, might have interfered with the execution of coordinated movements. Nurses can inform mothers of changes they can expect in their newborns' behavior.