Stages of Whelping
The parturition or whelping can be divided in different 3 stages.
The Stage I “preparation for whelping”. It averages approximately 6-12 hour long but can be as long as 36 hours. The bitch is usually restless and may show nesting behavior. She is nervous, panting, anorexic, and may tremble or shiver. You may see a temperature drop 1°C about 24 h before stage II in approximately 85% of bitches. This temperature drop is related to prostaglandin release and the abrupt decline in progesterone. It can also be identified with uterine monitoring (Whelpwise®)
Stage II of whelping “expulsion of fetuses”. Stage II is the active propulsive stage when the bitch pushes the puppies out. It lasts approximately 20 minutes to 1 hour per puppy but, no more than 2 hours should elapse between each puppy born. Stage II usually lasts a total of 3-6 hours but, may be as long as 24 hours total. Abdominal contractions are strong and coordinated. The “water bag or sac” may be seen first, then the pup with or without the covering of the amniotic sac. Puppies may present cranially or caudally. You ordinarily see passage of a neonate every 30 to 60 minutes. You should see passing of the first pup within 4 hours of labor onset, and the bitch should deliver pups at least every 2 hours thereafter. The bitch should tear away the amniotic sac and lick the neonate to stimulate respiration. If the bitch ignores the pup, tear away the sac and rub briskly with a towel. You may need to aspirate fluid from the pup’s respiratory tract.
Stage III of whelping “expulsion of placentas”. Placentas usually pass 5 to 15 minutes after each pup is born. You may see pup-placenta-pup-placenta or pup-pup-placenta-placenta. The bitch may eat them; they have no known physiological value, and may cause vomiting and diarrhea. Differentiation between resting in Stage III and completed parturition is difficult. You may need to take radiographs or ultrasound the bitch to be sure. Best to have films taken that last week of pregnancy!
Dystocia is a term used to describe a difficult or abnormal birth (“dys” = difficult, “tokos” = birth). This encompasses any problem in the birthing process ranging from severe (uterine torsion) to mild (prolonged labor). Dystocia can occur in any bitch regardless of breed or age. Dystocia can be caused by either maternal factors or fetal factors or a combination of both. Maternal factors which can cause dystocia include small pelvic size, small birth canal, or uterine inertia. Fetal factors which can cause dystocia are increased fetus size or wrongly positioned fetus.