constipation in neonates

Last edited 08/2023 and last reviewed 10/2023

Up to 90% of neonates pass meconium in the first 24 hours of life, the remainder usually pass meconium before 36 hours. There are a variety of important reasons that a neonate may be constipated (constipation in newborns can be defined as distress on passage of hard stools ordinarily fewer than three times a week (1)), and especially in the sick neonate it pays to have a high index of suspicion.

Red flags for constipation in a neonate - for immediate referral to paediatrician (1,2,3)

Symptoms that commence from birth or in the first few weeks

  • failure or delay (>first 48 hours at term) in passing meconium
    • a baby with delayed passage of meconium and subsequent constipation should be referred to a paediatrician or paediatric surgeon for assessment of gut motility and Hirschsprung disease; these conditions will inevitably worsen with time and lead to medical emergencies (1)
  • ribbon stools, leg weakness or locomotor delay
  • abdominal distension with vomiting
  • abnormal examination findings including:
    • abnormal appearance of anus
      • abnormal appearance/position/patency of anus: fistulae, bruising, multiple fissures, tight or patulous anus, anteriorly placed anus, absent anal wink (3)
    • gross abdominal distension
    • abnormal gluteal muscles, scoliosis, sacral agenesis, discoloured skin, naevi or sinus, hairy patch, or central pit
      • abnormal: asymmetry or flattening of the gluteal muscles, evidence of sacral agenesis, discoloured skin, naevi or sinus, hairy patch, lipoma, central pit (dimple that you can't see the bottom of), scoliosis (3)
    • lower limb deformity including talipes
      • deformity in lower limbs such as talipes
      • abnormal neuromuscular signs unexplained by any existing condition, such as cerebral palsy (3)
    • abnormal lower limb reflexes or neuromuscular signs unexplained by existing conditions
    • other symptoms that cause concern (1,2)

Reference: