Normal term babies often have hypoglycaemia especially in the first 24 hrs of life but without any sequelae, as they can utilise alternate fuels like ketones and lactate. There is no agreed definition of neonatal hypoglycaemia but a figure of < 2.6 mmol/L is used in many guidelines.

Transient hypoglycaemia in the first hours after birth is common.

Persistent/severe hypoglycaemia may be caused by:

• preterm birth (< 37 weeks)
• maternal diabetes mellitus
• IUGR
• hypothermia
• neonatal sepsis
• inborn errors of metabolism
• nesidioblastosis
• Beckwith-Wiedemann syndrome

Features

• may be asymptomatic
• autonomic (hypoglycaemia → changes in neural sympathetic discharge)
  • 'jitteriness'
  • irritable
  • tachypnoea
  • pallor
• neuroglycopenic
  • poor feeding/sucking
  • weak cry
  • drowsy
  • hypotonia
  • seizures
• other features may include
  • apnoea
  • hypothermia

Management

Management depends on the severity of the hypoglycaemia and if the newborn is symptomatic