ISSN 2398-2969      




  • Definition: difficulty delivering fetus(s) from the uterus through the birth canal (vagina, vestibule, vulva) normally resulting in birth.
  • Outcome: fetal and/or maternal morbidity and mortality, fading neonates, post-artum metritis.
  • Cause: fetal, maternal, combination.
  • Fetal:
    • Fetal abnormalities (hydrops fetalis, anasarca, hydrocephalic, twins).
    • Abnormal fetal position (fetal dorsum normally closest to dam dorsum; fetal ventrum closes to dam dorsum problematic) or posture (diving stance is normal, head elevation and shoulder flexion problematic).
    • Fetus exiting one horn and entering the other, blocking entrance into the uterine body.
    • 50% of canine fetuses are caudad (breech in humans) presentation, 50% cephalad, considered normal variation. Caudad can be problematic if pelvic limbs are in flexion.
  • Maternal:
    • Uterine inertia (primary Primary uterine inertia, secondary), herniation, adhesins, torsion, hydrops, lack of allantoic fluid, rupture.
    • Birth canal abnormalities: steep pelvic floor (brachycephalics), vaginal septum, stricture, vulvar edema.
  • Combination:
    • Mismatch between fetal size and birth canal dimensions (brachycephalics, chondrodystrophics, small litter size in breeds with litters typically >6 fetuses).
    • Singleton pregnancy: eventual fetal oversize +/- failure to initiate whelping (lack of fetal stress) causing prolonged gestation.
  • Treatment: depends on cause/type of dystocia. Supportive and specific (see below).
  • Prognosis: guarded to good.



  • Maternal vs Fetal (see above); combination of maternal and fetal causes most common.


Deviation from normal labor

Stages of normal labor
  • First: uterine contractions increasing in frequency and duration. Normally 12-24 h in duration. Preceded by temperature drop to less than 99°F (37.2°C) accompanying luteolysis and progesterone decline to <2 ng/mL, occurring 12-24 h earlier.
Note: no external contractions of abdominal effort are visible in Stage 1.
  • Second: uterine contractions + abdominal efforts → neonatal delivery.
Note: uterine contractions are accompanied by visible external abdominal contractions in Stage 2.
  • Third: placental delivery (normally with fetus, can occur up to 24 h after).
    • Bitches normally transition from stage 2 to stage 3 until entire delivery is complete.


This article is available in full to registered subscribers

Sign up now to start a free trial to access all Vetlexicon articles, images, sounds and videos, or Login


This article is available in full to registered subscribers

Sign up now to start a free trial to access all Vetlexicon articles, images, sounds and videos, or Login

Further Reading


Refereed papers

  • Recent references from PubMed and VetMedResource.
  • O'Neill D G, O'Sullivan A M, Manson E A et al (2019) Canine dystocia in 50 UK first-opinion emergency care veterinary practices: clinical management and outcomes. Vet Rec 184, 409 PubMed.
  • Gendler A, Brourman J, Graf K, Richards J, Mears E (2007) Canine dystocia: medical and surgical management. Compend Contin 29 (9), 551-62 VetMedResource.
  • Bergstrom A, Nodtvedt A N, Lagerstedt A S, Egenvall A (2006) Incidence and breed predilection for dystocia and risk factors for cesarean section in a Swedish population of insured dogs. Vet Surg 35 (8), 786-791 PubMed.
  • Davidson A P (2001) Uterine and fetal monitoring in the bitch. Vet Clin Small Anim Pract 31 (2), 305-313 PubMed.
  • Eneroth A, Linde-Forsberg C, Uhlhorn M & Hall M (1999) Radiographic pelvimetry for assessment of dystocia in bitches - a clinical study in two terrier breeds. JSAP 40 (6), 257-264 PubMed.
  • Darvelid A W & Lindeforsberg C (1994) Dystocia in the bitch - a retrospective study of 182 cases. JSAP 35 (8), 402-407 VetMedResource.

Related Images

Want more related items, why not
contact us

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!


To show you are not a Bot please can you enter the number showing adjacent to this field