The entire birthing process is seldom difficult and normally proceeds without human intervention, except in brachycephalic breeds such as Bulldogs. During stage one, which lasts 6 to 12 hours, involuntary uterine contractions dilate the cervix. The bitch may appear restless or uncomfortable, but exhibits no other signs.
In stage two, involuntary uterine contractions become more forceful. One uterine horn contracts and expels a puppy into the body of the uterus. The uterus contracts and pushes the presenting part of the puppy against the cervix. This stimulates active labor, with voluntary tightening of the abdominal wall muscles and purposeful straining. At this point the dam may become anxious and begin to pant and lick at her vulva. She may vomit. This is a normal reflex and should not be taken as a sign that something is wrong. Bitches usually deliver lying down, but some may stand or squat.
The cervix opens into the vaginal birth canal. When the cervix is completely dilated, the puppy slides into the vagina and the water bag around the puppy can be seen bulging through the lips of the vulva. In some cases the bag ruptures before the puppy is born. If so, a yellow or straw-colored fluid is passed. After the water bag breaks, the puppy should be delivered within a few minutes. Dark green fluid from placental wastes called biliverdin will be passed, but normally the puppy comes first.
About 70 percent of puppies are born in the diving position, with feet and nose first. After the head is delivered, the rest of the puppy slides out easily. The mother instinctively removes the fetal membranes and vigorously licks the puppy’s face to clear fluid and mucus from his nose and mouth. As the puppy gasps, the lungs inflate and breathing begins. The dam now severs the umbilical cord by shredding it with her teeth.
No attempt should be made to interfere with this normal maternal care. It is an important part of the recognition process and mother-puppy bonding. However, if the mother is occupied with another puppy and fails to remove the sac around the puppy, you should step in and strip away the fetal membranes to allow the puppy to breathe. Similarly, if the cord is severed too cleanly or too close to the puppy’s navel, it may continue to bleed. Be prepared to clamp or pinch off the cord and tie a thread around the stump.
After the mother severs the cord, the stump of each puppy should be disinfected with iodine or some other suitable antiseptic. This step helps to prevent umbilical stump infection.
During stage three labor, the placenta is expelled. A placenta is passed within a few minutes after the birth of each puppy. The dam may consume some or all of the placentas. This instinctive reaction may stem from behavior in the wild, where it is important to remove the evidence of birthing. Consuming the placentas is not essential from a health standpoint. In fact, ingesting several placentas can cause diarrhea. You may wish to remove some or all of the placentas. However, be sure to count them. If the number of placentas is less than the number of puppies, notify your veterinarian. A retained placenta can cause acute postpartum metritis.
Normally, the next puppy will be born from the opposite uterine horn. As the dam prepares for the second puppy, remove the first puppy and place him in a warm box. This way, the mother will not accidentally roll on the pup while she is distracted by the next birth. Between births put the puppies back on the dam’s nipples. Their sucking action stimulates uterine contractions and helps bring on the colostrum, or first milk of the dam. This colostrum contains maternal antibodies that protect the pups against infectious diseases.
Most puppies are born at intervals of 15 minutes to 2 hours apart, but this varies. The average time to whelp a litter of four to six puppies is six to eight hours, but large litters can take considerably longer. Dams who are whelping their first litter often take longer than experienced dams. Active straining returns 5 to 30 minutes before the delivery of the next pup. Occasionally the interval between puppies is as long as three to four hours. But if you suspect that the mother has not finished delivering all her puppies and she rests for more than four hours, or if she actively strains for 30 to 60 minutes without delivering a puppy, notify your veterinarian without delay.
Twelve to 24 hours after the dam has delivered her last puppy, have her examined by your veterinarian to be sure there are no retained puppies or placentas. An oxytocin injection (breeders call this a pit shot) may be given to clear the uterus. This also stimulates the letdown of milk.