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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Dystocia (or egg-binding) is common in reptiles (especially chelonians) and there are several possible causes which must be differentiated.


The signs of dystocia in reptiles are mainly non-specific and include :

  • Cloacal discharge (abnormal) - may be haemorrhagic, 
  • Dyspnoea
  • Hindleg weakness
  • Inappetance
  • Lethargy
  • Oedema of the distal extremities
  • Regurgitation of food
  • Restlessness
  • Straining
  • Weight loss

Egg-laying reptiles may lay part of a clutch but still retain some eggs.


Radiography or ultrasound is helpful to identify retained eggs or young in the uterus.


There are several causes of dystocia in reptiles that have been suggested including the following :

  • Malnutrition
    • Calcium deficiency - causes oviduct atony, and is most likely to occur in reptiles that do not eat whole vertebrate animals
    • Renal secondary hyperparathyroidism can result in calcium deposition in oviduct with consequential impaired function
    • Obesity
  • Environmental conditions
    • Low environmental temperature - many reptiles will not lay their eggs unless the ground temperature is adequate
    • No "private" area for the reptile to nest in
    • Incorrect lighting periods for the species
    • Recent change in the environment
    • Inadequate exercise
    • Inadequate depth of substrate in which to dig a hole to lay eggs
    • Presence of aggressive or competitive individuals if kept in a group
  • Oviduct infections
    • Usually secondary to dystocia but have been reported as a cause :
      • Monocercomonas spp in a boa caused foetal death and dystocia
      • Bacterial septicaemia may cause retention of eggs
  • Egg abnormalities - several types of abnormality have been associated with dystocia :
    • Large eggs - a common cause
    • Mishapen eggs - a common cause
    • Joined eggs
    • Excessive shell wall thickness
    • Calcified defects in the shell wall
    • Infertile eggs - usually resorbed or passed out, but they can cause dystocia
    • Damage to eggs in utero - eg trauma
  • Trauma during pregnancy
  • Foetal death in utero
  • Endocrine disorders 


Treatment of dystocia requires correction of any underlying problems (see above) and one or more of the following techniques :

  • Lubrication of the cloaca with sterile gel and manipulation to assist passage of the eggs or fetuses
  • Warm water baths may encourage delivery
  • Parenteral administration of calcium and oxytocin (or vasotocin) to induce contraction of the oviduct
  • Percutaneous ovocentesis may allow the collapsed eggs to be passed or removed successfully...but there is a risk of egg-yolk peritonitis developing with this technique
  • Surgical removal through a laparotomy may be needed in cases refractory to other forms of treatment..again rupture of eggs and leakage of yolk into the abdominal cavity must be avoided.


Updated October 2013