Canine dystocia is the veterinary term to mention one or several birth difficulties during the female dog’s labor and delivery of her litter of puppies. Dystocia in dogs includes, for example, a stalled labor, a blocked puppy, a malpresentation, etc.
Most dog breeders go through their litters, one after the other, without ever having one of their female dogs facing such challenges during the pregnancy, labor, or delivery. Nature generally takes care of everything and dogs manage smaller inconveniences very well on their own. However, it may happen that one day, one of your females is not giving birth to all her puppies as expected, or does it after a struggle.
If you are planning to breed dogs, you must be aware of the different types of birthing difficulties in dogs so you can prevent them better, and act promptly if you see some symptoms or signs. Canine dystocia is a bucket term and englobes very different birthing issues that we’re detailing in a below section.
What is Canine Dystocia?
Canine dystocia means a difficult or abnormal whelping of puppies. When dystocia occurs, it may originate from the dam or the puppies. A dam’s pregnancy normally lasts 63 days, with toy breeds a bit shorter and larger breeds a bit longer. Some breeders will start taking the temperature of the dam two weeks before the expected due date to try to ascertain the day labor begins. A normal temperature of a dog is 101-103 ℉. When a dam’s temperature drops to 99 ℉ or below labor is twenty-four hours from beginning.
Labor is divided into three phases.
- The first phase it is the longest one. Contractions begin and the birth canal thins and dilates. The dam may be restless and may display nesting behavior, e.g. seek out or dig out a place to give birth.
- In the second stage, contractions should be strong and, in most dams, visible. The dam will be in obvious discomfort and will pant, tremble, and maybe vomit.
- In the third stage (which usually overlaps the second) the puppy placentas are expelled.
Problems can arise in any of the three phases. The majority of the cases of dystocia arise from the dam (around 60%). The time for labor varies for individual dams and for different breeds. Dams with previous litters usually have shorter labors. How long a dam should be allowed to labor before the veterinarian is called differs among the various sources. Most will agree that the veterinarian should be called for a dam that has labored with obvious contractions for more than 12 hours without a whelping.
Dystocia related to the puppies usually means the birth process (delivery) is inhibited by the malposition of a puppy, the presence of a dead puppy, or by a birth canal too small to pass a large puppy. Some small and toy breeds routinely produce puppies with heads too large to pass through the birth canal. These kinds of problems are diagnosed by the use of ultrasound or x-ray.
Different Types of Birthing Difficulties
Below is a list of the most common types of dystocia that can arise in a female in labor during the whelping of her puppies. These are very much considered reproductive emergencies by most veterinarians, as beautifully explained in Jeanette Yamamoto’s presentation for the Animal Specialty & Emergency Center (PDF here).
Uterine Insufficiency (or Inertia)
One issue a dam may have is uterine insufficiency or inertia. In this condition, the dam has too few effective contractions. Veterinarians divide uterine insufficiency into two types: primary and secondary.
- In the primary, the dam doesn’t begin an active labor. In other words, a temperature drop and the dam’s behavior indicates labor should be happening, but no puppies are whelped.
- The secondary uterine insufficiency occurs when the dam starts labor with strong contractions and then the contractions weaken or become too episodic to deliver all the puppies. In primary uterine insufficiency, no puppy is born while in secondary a puppy or puppies may have.
A veterinarian should be called if after four hours the next puppy has not been whelped. Failure for the puppy to appear could be caused by uterine insufficiency or some problem with the puppy. Uterine insufficiency accounts for 40 to 70% of all maternally caused dystocias.
Toxemia (also called preeclampsia, milk fever) is caused by a drop in blood calcium during labor or a couple of weeks after whelping. The condition can rise to crisis potential and death to both the dam and any puppies in utero. The dam’s blood pressure will suddenly rise, and kidney failure and convulsions will cause death if it is not treated. Symptoms of toxemia include rigid limbs, tremor, muscle spasms, increased salivation, and panting.
It is important to know that while low blood calcium precipitates the condition, excessive dietary supplementation of calcium during pregnancy predisposes the dam to it.
Dogs do have diabetes, but at very low incidence as compared to humans. Diabetes (hyperglycemia) in dogs is divided into two types. One is caused by a failure of the pancreas because of a congenital defect to produce enough insulin for metabolism. The second type is called insulin resistance disorder. In this condition, the pancreas does not respond to some condition that increases the need for glucose in the cells. Gestational diabetes is of the latter type. After the stressor is over (like pregnancy), the bitch will return to normal.
A dam with gestational diabetes may appear lethargic and will be very thirsty. She may lose weight, excessively eat, and have a sweet smell to her urine. Gestational diabetes can cause the death of the dam and the puppies. It is treatable with insulin injections and meal management. It is very rare in dogs in general. However, some breeds including Samoyeds, Cairn terriers, and Dachshunds seem to show a higher risk for it.
A uterine infection will often spread to the puppies. Puppies can be killed in utero (stillborn) or can be born sickly. The kind of infectious agent will determine the severity and treatment of the condition.
Brucellosis is an infection caused by the bacterium Brucella canis. This infection can cause miscarriage, late-term abortion, stillbirth, and very sick puppies. It is an infection that is almost impossible to cure. Dogs diagnosed with it are usually euthanized because humans can also catch it from dogs. There is a screening test for brucellosis, and both the bitch and stud dog should be tested prior to mating.
Other bacterial infections include salmonella and mycoplasma. These are treatable by antibiotics. Unfortunately, though, they may not have caused a bitch to be ill enough prior to mating. Sometimes the infection is only first diagnosed when it causes a late-term abortion or the in utero death of a puppy.
Dogs may have viral infections. The canine herpes virus may cause stillbirth. This is a sexually transmitted disease in dogs. The adult dog may have few or no symptoms. In fact, the infection may be dormant and become activated with the stress and strain of pregnancy. Puppies will be infected in utero. They may be whelped and appear fine, but the virus will attack their livers. Within a couple of days, the puppies will die. There is no cure for this infection.
Birth Canal & Reproductive Tract Issues
The whelping may be impeded by structural problems in the dam’s reproductive tract. These impediments can be a congenitally too small pelvis or an injury to the pelvis that did not heal correctly. Tumors (benign and cancerous) and cysts all can cause whelping as well as infertility. These problems may be in any of the parts of the reproductive tract including the uterus, vagina, etc. Vaginal strictures are adhesions or growths that result in the tightening of the vagina. They can impede the passage of the puppies. Also, an inguinal (abdominal) hernia can push on and obstruct the birth canal.
Torsion of the uterus occurs when the uterus twists on its axis. It happens either as the result of a lack of fetal fluid or as a result of some kind of trauma (such as a fall). The lack of cushion for the fetuses and the torsion itself can result in the loss of the puppies and the dam. The dam will have a foul-smelling discharge, and fever. It is treated by c-section.
Malpresentation in dogs does not mean breech. Forty percent of puppies are whelped in the tail first position. A malpresentation would be a puppy in a sideways position or a puppy that has extended a limb to cause an obstruction. Sometimes a veterinarian may be able to make a manual reposition of the puppy. If the birth canal has been fully thinned and dilated, a vet may be able with lubrication insert fingers into it. Singletons which are more common in the toy breeds may be overlarge for the birth canal.
Dead fetus/Defects in fetus or puppy
A dead fetus can stall a labor in the dam. Sometimes a fetus dies for no apparent reason. Only about 1% of dystocia due to the puppies is from a dead fetus.
The presence of a dead fetus can endanger the delivery of the other puppies. A genetic defect can be a one-time mutation or it may be a problem in the genetics of the dam or sire. Any defect that occurs a second time with a different sire may be a reason to retire the bitch from the breeding program.
Causes of Dystocia in Dogs
The below common causes of canine dystocia are proven right by the frequent diagnosis of birthing problems in specific breeds (small and toy breeds, but also overweight dogs, and brachycephalic breeds). The reasons why dystocia and birthing difficulties affect a breed of dogs more than another, or a given female dog more than another, are multiple. Of course, there is bad luck like in most fields of life, but you can generally narrow the cause of dystocia down to a few potent factors.
Some conditions that result in dystocia are more common in older dams. Older dams have an higher incidence of infection. This higher infection rate is not a cause per se, but rather a statistical correlation that each time a bitch is mated, she runs the risk of picking up an infection.
Also, some obstructive problems develop over time. Tumors of the reproductive tract are more likely in an older bitch. The risk of secondary uterine insufficiency and gestational diabetes increases with the age of the dam. Gestational diabetes more frequently occurs in middle age to old bitches.
Older bitches and studs have higher incidence of genetic or congenital problems in the offspring. The degradation in the ovum and sperm increases the incidence of fetal death, and the defects in the puppies that give rise to dystocia.
In addition, bitches that are bred at a very young age or before they have reached full maturity are at greater risk for dystocia. Most breeders will not breed until a bitch has had at least two heat cycles. Immature ova are more likely to produce birth defects, prematurity, and smaller and more sickly puppies.
Obesity predisposes a dam to gestational diabetes, and may make it hard to spot when active labor begins. A great deal of time may pass before dystocia is apparent. The delayed intervention can mean the loss of puppies, and risk the life of the dam. A bitch should be in top physical condition before being bred. Pregnancy is not the time for dieting.
Brachycephalic and Toy Breeds
The breeds with the large heads and short muzzles like Bulldogs, Boston Terriers, Boxers have rates of surgical delivery so high that c-sections are the norm. Over eighty percent of English bulldogs are surgically delivered. These breeds just can’t safely whelp naturally. The birth canal is just too narrow. Toy breeds, also, have high rates of surgical delivery, such as Chihuahuas, and Pomeranians.
Indeed, abrupt changes in a dam’s environment before she goes into labor will often cause a more difficult birth than normal. If a dam is subjected to some kind of environmental stress, the likelihood of prematurity or other dystocia is increased. Some dams are more high strung and nervous than others. The waning days of a pregnancy are not a good time for a change in the housing of the dog or extremes in temperature or the introduction of a competing canine into the household. A premature labor can result in stillbirths and the death of an entire litter. Environmental stressors, also, increase the chance of the dam developing gestational diabetes.
[pullquote-right]Age, obesity, size, brachycephalic breeds, and environmental stress are all factors to consider when talking about canine dystocia and birth difficulties.[/pullquote-right]
This is why we highly recommend you to set up your female dog’s whelping box early on in her pregnancy, ideally in a quiet spot in your home where children are rarely around.
Breeds With Birthing Difficulties
The rate of cesarean delivery by breed gives a good snapshot of which breeds have the highest incidence of dystocia.
A 2004’s study of over 151 breeds involving over 13,000 bitches looked at the incidence of c-section. The ten breeds with the highest rates of c-sections were as follows:
- Boston Terrier (92.3%),
- Bulldog (86.1%),
- French Bulldog (81.3%),
- Mastiff (64.6%),
- Scottish Terrier (59.8%),
- Miniature Bull Terrier (52.4%),
- German Wirehaired Pointer (47.8%),
- Clumber Spaniel (45.2%),
- Pekingese (43.8%), and
- Dandie Dinmont Terrier (41.4%).
Toy breeds that are bred to be very small (under 3 pounds) frequently require surgical deliveries. Over a third of Chihuahuas require cesarean sections, and you can see stats about the frequency of cesarean sections in other dog breeds, too.
Prevention of dystocia
A successful whelping in which dam and puppies come out healthy, and without the need for surgical delivery begins with a bitch in good health prior to mating. A fit bitch that is neither too old or too young is the foundation for the best outcomes. All shots and screenings should be conducted on her and the stud. She should be fed a good diet, and be in top shape. The dam should be introduced to her whelping box a few weeks before the due date. She should be given time to acclimate to it, and her environment should be as stress-free as possible.
One thing that can be done to lower the chances for dystocia is to have good information. Some breeders will take two temperatures a day in the last two weeks of pregnancy or have the veterinarian check out progesterone levels to help pinpoint when labor should begin. An x-ray or ultrasound in the last two weeks of pregnancy will let an owner know how many puppies to expect in the litter, and help assess the size of the puppies and their viability. Blood chemistry can help with early diagnosis and treatment of health problems like eclampsia and gestational diabetes.
Treatment & Recovery of Canine Dystocia
The treatment of canine dystocia depends on the cause. A pregnancy loss caused by the contraction of some bacterial infection may be completely treatable by an antibiotic. It may never recur. An obese bitch’s diet can be managed so that she is in tip-top condition the next time around. A benign cyst may be surgically removed. A dam may have secondary uterine insufficiency in a first litter, but subsequent litters with shorter labors may be problem-free.
A veterinarian may treat uterine insufficiency through the use of intravenous oxytocin. This hormone stimulates contractions. A veterinarian will be careful to determine that there are no obstruction problems with the delivery. The hormone will cause strong contractions in the dam that may injure a malpositioned puppy. Uterine insufficiency is the most common cause of dystocia arising from the dam. It is likely to recur in future litters especially in middle to older bitches.
Gestational diabetes, also, is likely to recur in future litters. A bitch’s diet should be a high quality one, weight controlled, and few changes should be made in the dam’s environment during the pregnancy. Bitches ideally should be retired from the breeding program if they are middle-aged. Although most cases of diabetes resolve after the pregnancy, there is a continuing risk of it not resolving as the bitch ages.
If a puppy dies in utero or dies shortly after birth, an attempt should be made to determine a cause of death. This information is vital to prevent a recurrence in subsequent litters. For example, some infections like canine herpes or brucellosis can’t be cured, and they can’t be prevented from killing in subsequent litters. Unfortunately, the bitch should not be bred with a diagnosis of these infections. A defect like a heart abnormality in the fetus could be a one-time problem, but if it has repeated in the bloodline there may be a need to reexamine the breeding stock.
Dystocia related to the breed is largely unavoidable. A veterinarian may not even recommend a natural labor be attempted in a breed like an English bulldog. In picking studs for toy dogs, it may decrease the chance of c section if the stud is not bigger than the bitch. The breeding of “teacup” toys increases the chances for prematurity, gestational diabetes, and puppies disproportionately large for the birth canal. These tiny dogs, in addition, have an increased risk of side effects and death from anesthesia.