• Low birth weight - less than 5.5 pounds (2500 grams)
• Thin, smooth, shiny, almost translucent skin
• Veins are easily seen through the skin (transparent skin)
• Wrinkled features
• Soft, flexible ear cartilage
• Body hair called lanugo
• Irregular breathing pattern
• Weak cry
• Usually inactive, may be unusually active immediately after birth
• Ineffective suck and swallow (poor feeding)
• Enlarged clitoris (female infant)
• Small scrotum, smooth without ridges (male infant)

The infant may have a low body temperature, develop rapid breathing, or exhibit poor respiratory effort.

Common tests performed on a premature infant include the following:

• Chest X-ray to determine lung maturity and onset of respiratory distress syndrome
• Blood gas analysis
• Serum glucose
• Serum calcium
• Serum bilirubin