The majority of time, when animals are giving birth, everything goes smoothly and new life/babies arrive. But, sometimes, animals in labor start having major difficulties that can result in very different situations and their lives and their babies lives may be in danger. Difficult labor or delivery is also called dystocia and can occur from a variety of different factors and need to be addressed early in the labor process so that a favorable outcome can be expected.
Stages of Labor
There are three stages of labor.
- Stage 1 is the start of uterine contractions, in which the cervix will relax and dilate and the amniotic sac will rupture (better known as the water breaking). Signs of this stage include restlessness, nervousness and nesting behavior from the mother animal (dam). This stage can last from 2-24 hours depending on what animal we are considering, her age and personality.
- Stage 2 involves the expulsion of the baby via strong contractions. This stage can be as short as 15 minutes or less (more common in horses) to 24 hours. Generally large/farm animals only have one to two babies, so delivery is considerably shorter, while our small animals usually have multiple babies, so it simply takes longer to expel them (my personal large litter is 17- one dog via C-section and one sow had this many!)
- Stage 3 is the delivery of the placental membranes. This stage can alternate with stage 2, as often a placenta is passed after each pup, while pigs usually have all the babies and then pass the membranes.
Causes of Dystocia
Maternal factors such as uterine inertia, which can be primary or secondary, pregnancy toxemia (more common in farm animals), age, obesity, previous pelvic trauma (hip fractures) and genetics play an important role in possible problems. Primary uterine inertia can be caused by inappropriate nutrition for the dam during the pregnancy or hormonal problem which may be genetic. Secondary uterine inertia is mainly because the dam is weak going into the labor process because of improper diet, age (can be seen with too young or too old), or with multiple babies and she is simply worn out from pushing (common in the toy breeds that have more than 2-3 babies). Genetics play an important role in dystocia especially in brachycephalic breeds (pugs, bulldogs, boston terriers) and toy breeds simply because of the size of the animal and the size of the babies’ heads. Abrupt changes in the environment near the time of labor, drug use (use of phenylbutazone, a pain killer used primarily in horses, can cause disruption by delaying the labor process), previous history of problems (may have adhesions, tears or hernias from previous delivery or C-sections), uterine torsion (more common in cattle), vaginal strictures (I’ve seen these in cattle, sheep and dogs), and uterine rupture (I’ve seen this more in cattle, but I have had it in goats and dogs).
Fetal factors include an over sized baby (can be due to overnutrition or genetics), abnormal positioning or orientation of baby within the birth canal, baby abnormalities/deformities, and death- a dead baby does not move in the uterine horn properly. Some of these can be controlled by careful breeding and a good genetics program in all species of animals. Using smaller breeding males (sires) in relation to the females (dams) and breeding at an appropriate age and size can be very important.
When to Seek Help
- Previous history of problems (in which case the animal probably shouldn’t have been bred again!).
- Strong contractions lasting more than 1-2 hours with no passing of a baby.
- Active labor after passing a baby lasting more than 2 hours without delivery of subsequent babies.
- Dam in obvious pain, weakness, has a fever, signs of systemic problem (jaundice).
- Abnormal vulvar discharge such as very dark blood or greenish in color.
- Prolonged length of gestation or too short; for example normal gestation in dogs is 57-72 days, so less than 56 days usually leads to premature or dead babies and longer than 72 days usually leads to large babies and the obvious problems with an over sized baby.
Assessing the Problem with Labor
The cause of dystocia must be determined-obstructive vs nonobstructive. Digital palpation through the vulva may help determine if an obstruction (baby is wedged in birth canal), stricture, or improper cervical dilation is evident. With cats and dogs, x-rays or ultrasound is usually indicated to determine placement, number, size and position of the babies. Ultrasound can further tell if they are alive as movement and heartbeats can be seen.
Treatment for Dystocia
if dam is not stressed, fevered and/or x-rays have ruled out obstructive problems, medical treatment can be tried. This may include injections of oxytocin, calcium gluconate and IV fluids may help to increase uterine contractions. Manual manipulations via hand (with large animals) or spay hook (in small animals) are often successful in moving the babies into proper position or delivery (I’ve had good luck with these procedures especially when the dam is not in good enough shape for surgical intervention (C-section). If dam is in obvious pain, stress or if medical treatments have not worked, a Cesarean section (C-section) may be indicated. This is far more common in small animals versus large/farm animals as economics come into consideration especially with cattle, sheep and goats.
Prevention of Dystocia
A good breeding program with any species is important. This includes proper age and size of dams and sires as well as the right physical characteristics/genetics of that type of animal. They should be checked for abnormal physical problems which may interfere with any gestation or labor and delivery. Many breeders of cats and dogs (especially toy and brachycephalic breeds) will x-ray late in pregnancy to determine size, number and possible positioning problems. Proper vaccination protocols are also important. With proper forethought, many problems can hopefully be avoided.