Which sign could indicate that a baby is not adapting well after birth?

Difficulty breathing is a significant indicator that a newborn may not be adapting well after birth. The transition from the intrauterine environment to life outside the womb is critical, and adequate respiratory function is essential for the baby's well-being. If a newborn exhibits signs of respiratory distress, such as grunting, retractions, or periodic apnea, it often suggests underlying issues such as inadequate lung expansion, fluid in the lungs, or other complications.

In contrast, stable vital signs would generally indicate that the newborn is adjusting well, high body temperature might suggest thermal regulation issues but not directly correlate with the adaptation to extrauterine life, and a startle reflex is a normal and expected response in infants, indicating that the nervous system is functioning appropriately. Thus, difficulty breathing stands out as a clear sign of possible adaptation issues following birth.