Dogs began having puppies long before humans came into their lives, so there's no vital need for intense, day-to-day management of your pregnant dog. It's much more important for owners to understand what's normal during their dog's pregnancy and to intervene when there are signs of trouble.
Assure Your Dog's Health
Have your dog examined by her veterinarian prior to breeding to make sure she doesn't have any health problems that might affect her pregnancy. Make sure she is current on all her recommended vaccinations to maximize the amount of antibodies she will pass on to her puppies. She must have negative tests for intestinal and blood parasites (such as hookworms and heartworm, respectively) and must not be a carrier for Brucella canis bacteria (a simple blood test will show this).
The Pregnant Dog
The average canine pregnancy lasts approximately 64 to 66 days. During the first two-thirds of her pregnancy, your dog will do best if fed her normal maintenance diet. The expectant mother's energy requirements won't change greatly until the third trimester, when her weight may increase by 15 percent to 25 percent.
Pregnancy diagnosis is usually first reliable around 18 to 19 days of gestation, depending on the method employed. Abdominal ultrasound can detect fetuses within 16 to 20 days of gestation; fetal heartbeat can be detected around 23 to 25 days.
Not every veterinarian has an ultrasound machine in the office, so some veterinarians check manually. Through the use of abdominal palpation, trained veterinarians can usually identify individual fetuses in the uterus beginning around 20 days of gestation.
After day 28, the uterus will become too large to allow accurate identification of individual fetuses by hand. The hormone relaxin can be measured in your dog's blood to determine if she's pregnant, but this measurement is only accurate after 30 to 35 days of gestation.
The fetuses will grow most rapidly during the third trimester; this is when the mother needs a higher-calorie diet (calories and nutrients should be 1 ½ times greater than the maintenance diet). Medications must be avoided during pregnancy, unless prescribed by your veterinarian (as with humans, always ask first to be sure).
Most dogs whelp (give birth) without any complications. Difficulties in whelping are most common in toy breeds and breeds with short snouts and large heads (such as English bulldogs). Dogs of these breeds may require Cesarean section surgery if pups cannot be delivered vaginally (through the normal birth canal).
Approximately one day before whelping, the level of progesterone in the blood, which has been high throughout pregnancy, falls to a level not seen since the dog first went into heat. Within 14 hours of this progesterone drop, there will be a fall in the dog's rectal temperature (normally around 100 to 102 degrees Fahrenheit; prior to whelping, the temperature may drop below 99 F). This temperature decrease is usually followed by labor within 12 to 24 hours.
The Stages of Labor
Labor consists of three different stages.
Stage I begins with the first contractions of the uterus and ends when the cervix is completely open and ready for puppies to pass out through the birth canal. Owners cannot usually see the contractions, but your dog may exhibit panting, restlessness, vomiting, anorexia (loss of appetite) and nesting behavior. Stage I may last from 6 to 24 hours. It's best to keep the environment quiet for your dog so as not to further excite her. Little else can be done for these completely natural events of whelping.
Stages II and III alternate with one another: Stage II ends with the delivery of a pup, whereas Stage III ends with the expulsion of the pup's placenta. It may take between 15 minutes and 4 hours between the deliveries of one pup and his placenta and the next. You shouldn't be concerned unless pups have not passed for longer than 4 hours or if your dog has been actively straining to deliver a pup longer than 30 minutes with no success. Contact your veterinarian or your local emergency hospital immediately should this occur.
Stages II and III of Dog Labor
Click on this video to watch a dog giving birth.
The new mother should vigorously clean each puppy as he's born. This helps to remove placental membranes, dry each puppy from maternal fluids and stimulate the puppy to breathe. This will also stimulate the mother's nursing instincts. The mother will usually eat the pup's placenta; this is natural. Approximately 40 percent of puppies are born breech (rear legs first). This isn't a problem unless the mother is straining excessively with little change in the pup's position. Any deviation from the normal whelping process should signal you to seek immediate veterinary advice.
Newborn Puppy Care 101
Assuming that the new mother has cleaned her pup of his placental membranes, the pup should be clean and dry within minutes of delivery. Always check for a normal breathing pattern and call your veterinarian immediately if there seems to be a problem. If the mother is not cleaning her pups, free them of their membranes immediately and call your veterinarian.
The environment that a newborn puppy is to be reared in should be set up well in advance of whelping. A whelping box should be placed in an area of the house that allows your dog and her puppies much privacy. The box should have walls tall enough to allow the mother – but not puppies less than 4 weeks of age – to exit. It should be made of a material that can be easily cleaned. Non-vertical sides (sides that slant outward) are often recommended so pups don't hurt themselves or one another as they try to climb the walls of their enclosure.
A heat source should be present since newborn puppies cannot regulate their body temperature very well. Environmental temperature should remain around 86 to 90 F during the first week of the puppy's life and gradually fall to 75 F over the next 3 weeks. The ideal humidity in the whelping box should be 55 to 60 percent. Drafts must be avoided.
Very soon after birth, puppies should begin suckling from the mother. Newborns have very low reserves of energy, so they must obtain fresh reserves from the milk. In addition, since very few antibodies come from the mother through the placenta (blood) before whelping, puppies must get infection-protecting antibodies from their mother's first milk. However, if puppies don't ingest the milk within 12 to 16 hours after birth, very few antibodies will be absorbed and the puppy will be susceptible to infections until he can produce his own antibodies after 4 weeks of age.