Dog Pregnancy: What to Expect

Pregnancy is a natural condition for dogs. For the most part, you can let your dog’s gestation run its course because she will instinctively know what to do. As a responsible pet parent, however, it’s still important for you to understand and anticipate what’s to come.  

Did you know dogs are only pregnant for about 63 days? During that time, you’ll need to monitor her condition, take her to the veterinarian, modify her daily routine, and help her prepare for the puppies. 

Basics of Dog Puberty and Pregnancy

First, it’s important to know whether your dog is able to get pregnant. The onset of puberty varies between dog breeds. On average, a dog’s first estrus (time in heat) occurs at approximately 6 months old. The first obvious signs of estrus in many cases are an enlarged vulva and bloody vaginal discharge.

A female dog can only become pregnant while she’s in heat, and this stage typically lasts for 10 to 14 days. You can anticipate signs of estrus every six to seven months, although it can take up to two years for her heat cycles to become regular. 

There are two ways for your dog to become pregnant. One is by accident—mating with a male dog (stud) she came into contact with. The other is through planned breeding. As a pet parent, you should be aware that if your female dog isn’t fixed, she always runs the risk of becoming pregnant. An in-heat female is extremely attractive to intact male dogs, which means they may take drastic measures to get to her. Therefore, it can be challenging to prevent accidental breeding. Spaying your dog is the best prevention against a litter of puppies.

Alternatively, if you plan to breed your dog, you need to understand that breeding is a responsibility that shouldn’t be taken lightly. Reputable breeders spend years studying the history of breed standards, development, and science that goes into it. 

Signs of Pregnancy and Dog Pregnancy Tests

If you suspect your dog is pregnant, make sure you pay attention to the correct signs. 

Within the first 30 days of pregnancy, these common symptoms may go unnoticed:

• Enlarged nipples
• Lethargy
• Increased appetite
• Vaginal discharge

Some dogs may also develop signs of “morning sickness” for a few days during early pregnancy. Your dog may eat less than usual and may even vomit once or twice. This stage is very brief, though, and does not always occur. You shouldn’t count on the presence or absence of “morning sickness” as a reliable indicator of pregnancy. 

In month two, signs of pregnancy typically become more apparent. Your dog may show behavior changes, weight gain along with an extended abdomen, and the need to pee more frequently.

The only way to determine if your dog is pregnant is through a vet visit, where they can perform a series of diagnostic tests. The further along in pregnancy your dog is, the more accurate these tests become: 

• Palpation: After day 25, your veterinarian may be able to palpate your dog’s abdomen and feel changes within the uterus. This is not always reliable, however, as the dog’s conformation and temperament play a big role in how effective this will be. 
• Ultrasound: Beginning as early as day 21, ultrasound can detect pregnancy. Ultrasound becomes even more reliable after day 30. 
• Blood test: Relaxin, a pregnancy hormone, may be detectable in the blood after day 30.
• X-ray: At 45 days of pregnancy, X-rays can be used to detect pregnancy and estimate litter size.

Main Stages of Dog Pregnancy

Dog pregnancy lasts for about nine weeks (63 days). During this relatively short gestation period, the puppies grow and develop at a rapid pace. Here are some of the big milestones to be aware of:

• Day 30: Your veterinarian should be able to detect fetal heartbeats on an ultrasound. 
• Day 45: An X-ray can reveal the number of puppies in the litter. A typical litter size is five to six puppies, although litter size can vary significantly depending on breed.
• Day 58: Your dog will start looking for a place to give birth (see “Preparing for the Birth” below). 
• Final few days: The puppies will move into the birthing canal, and your dog may appear restless and begin pacing. 

Depending on her overall health, and the toll that whelping (i.e. birthing puppies) and lactation have taken on her body, it is possible for your dog to get pregnant during her next estrus. If your dog became pregnant by accident, this is a good time to discuss options for spaying her.

Changing Your Dog’s Routine

Unless your veterinarian tells you otherwise, one or two trips to the vet should be enough during your dog’s pregnancy. 

The first visit, in the case of a planned pregnancy, is to confirm the pregnancy via ultrasound. An ultrasound is typically performed at day 30. Not all veterinarians have ultrasound available, so you may be referred to another practice for this test. Costs associated with ultrasound vary by practice but typically range from $250 to $500.  

The second pregnancy test (or the first, in the case of many unplanned pregnancies) is an X-ray to determine the size of the litter. This X-ray is typically performed at 45 days of pregnancy. Typical costs range from $150-$250. 

Your veterinarian will also give you advice on how to modify your dog’s routine—including exercise, medication, and dietary changes. 

Your pregnant dog should be fed a high-quality puppy food in small, frequent meals. Puppy food will ensure that your dog receives the calories and nutrients that are needed to support her pregnancy. Talk to your veterinarian to determine how much to feed your dog and how much weight gain is desired during pregnancy. Desired weight gain varies depending on your dog’s pre-pregnancy condition. 

Your veterinarian may want to administer vaccines if your dog is not up to date. Talk to your veterinarian to determine which vaccines are safe to administer during pregnancy. Flea and tick treatments and heartworm prevention medication should continue as usual throughout her pregnancy. Common parasites, such as roundworms, can transfer from the mother to her puppies, so broad-spectrum protection is crucial during pregnancy. 

Some prescription medications may be harmful during pregnancy, so talk to your veterinarian prior to breeding if your dog receives prescription medications on an ongoing basis. While you should never administer medication to your pet without the guidance of your veterinarian, this recommendation is especially important during pregnancy. 

Preparing for Birth

You’ll need to establish a space within your home for your dog to safely and comfortably give birth. Do this by creating a whelping box that’s big enough for her (and the pending puppies) to fit in. Ensure it’s lined with newspapers or a blanket you don’t mind parting with, as well as a heat source for the newborn puppies. This can be an electric blanket, floor warmer, heat lamp or hot water bottle. She should start spending time in the whelping box about a week before giving birth.

As the dog’s due date arrives, be prepared to contact your veterinarian or a veterinary emergency clinic. Most dogs are capable of handling the process themselves—with you nearby for support—but emergencies do arise and some dogs require a C-section or other interventions.

You should know how many puppies to expect, based on your dog’s X-rays. Knowing the litter size ahead of time will help you monitor your dog’s progress, and whether she’s having trouble. 

If any of the following circumstances occur, contact your veterinarian immediately:

• 60 minutes of active contractions with no puppies produced
• Four hours between puppies (if you know, based on X-rays, that there are puppies remaining)
• Signs of extreme pain

When the puppies are born, they will be covered in a membrane. This membrane must be cleaned away. Typically, the mother will do this by licking the puppy. If she does not, you should remove the membrane and rub the puppy with a clean, dry towel. You will also need to remove the umbilical cord if she does not do so. (Talk to your veterinarian ahead of time to find out what steps to take, should this situation occur.) If possible, keep the mother from eating the placenta. It is not harmful to her, but may cause vomiting. 

Preventing Pregnancy in Dogs

If you don’t plan on responsibly breeding your dog, it’s medically advisable to have her spayed before her first estrus cycle. This is the only way to ensure she doesn’t have an unwanted pregnancy. And, in fact, there’s evidence to suggest spayed dogs live longer, healthier lives (1).

Spaying provides a number of medical and behavioral benefits. First of all, spayed dogs are less likely to roam, making them less likely to be hit by a car or suffer other types of trauma. Additionally, spaying your dog will prevent or decrease the likelihood of serious medical problems. 

Intact female dogs have a 25 percent chance of developing mammary cancer at some time during their lives, while the risk of mammary cancer in a dog spayed before her first heat cycle is only 0.5 percent (2). Intact dogs also have a 25 percent chance of developing pyometra, a life-threatening uterine infection; spaying your dog prevents this infection (3).

Related Conditions 

• Infertility
• Pyometra