Pregnant Dog & Worms: Advice and Best Practices

So your wondering whether you should worm your dog when there pregnant? De-worming is essential for your pup in normal circumstances, let alone through pregnancy. 

Below, we take a look at whether it is safe to worm your pregnant dog and the correct dosages.  

Lets jump straight in...


Congratulations; your dog is pregnant and in a few weeks’ time you will be the proud owner of a litter of cute puppies. However, did you know many puppies are born with worms which are passed from the mother either in the womb, the placenta or in the milk after birth.

Pregnant female dogs need to be de-wormed. They are using a lot of body energy to sustain their puppies as they grow. An infestation of worms plus a growing litter can be extremely harmful for an expectant dog.

Here, we take a look at why worming pregnant dogs is important, not only for the mother but for the pups too. First though we’ll give you some facts about pregnancy in dogs

What to do when your dog is pregnant for the first time

If you are thinking of breeding your K9-companion it is essential to take her to the vets before mating. That way, she can be given a thorough health check and the vet will probably suggest you de-worm her.

Once the deed is done, the mating that is. You will need to return at 28 days for a diagnostic test, this will entail the vet palpitating the stomach where he will feel, if the dog has conceived, small fluid filled sacks.

(Do not try feeling for these yourself, in case you damage the pups)

Alternatively, an ultrasound scan can be done between 25-35 days into gestation.

After 30 days your vet can do a hormone test. The hormone relaxin is only released during pregnancy, so this is a simple test to determine whether your furry friend is expecting.

Like human pregnancies, there are signs which could indicate puppies are on the agenda
  • Weight Gain
  • Increased Appetite
  • Bigger Nipples

Is it safe to worm a dog which is pregnant?

You might be wondering; If we are told, as we often are; to avoid giving pregnant dogs medications unless absolutely necessary, then why is de-worming allowed?

After all there are some pretty powerful chemicals in some worming products.

Most vets agree that it is perfectly safe to worm a pregnant dog, as long as certain guidelines are followed.

Not all products are created equal, so read the ingredients and small-print.  Many recommend Panacur, this contains fenbendazole which is safe and effective against whipworms, roundworms and hookworms.

If you are worried about de-worming a pregnant bitch or have any questions you should consult your veterinary surgeon who will advise you on the best course of action.

Symptoms To Look Out For:

  • Always Hungry
  • Vomiting
  • Scooting
  • Loose Stools
  • Lethargy
  • Weight Loss

How To Give & Dosage

You should always administer worming tablets according to your dog’s weight. Of course, if she is pregnant, this will have increased by around 15%-20% so take that into account.

Nowadays most are chewable and pleasantly flavoured which means they can be given as a treat.

Top tip: (If your dog doesn’t like taking pills you can hide it in some peanut butter or cheese)

The good news is; pregnant dogs are usually hungry and will chow down on pretty much anything

If she can’t take them, you will need to use a liquid de-wormer such as Panacur liquid. Alternatively, your vet may give her an injection.

It is important to follow the instructions to the letter, if you can’t find specific instructions for “canine mums to be” don’t use the product

Generally speaking a liquid dose will be 1 teaspoon (or 5ml) for each 10 pounds of body weight. Some dogs will lap it right off the spoon and with others you may need a syringe if it doesn’t come with a pipette.

You will then need to administer another dose either 2 weeks afters the puppies have been born.

What To Expect After

Worming any dog has a similar effect, the treatment will either destroy the worms internally or paralyse them, so they are then passed when your pet goes to the loo.

Common side-effects are nausea and diarrhoea; this is because the parasites will cause inflammation or irritation when passing through the gut, which can cause an upset stomach.

Your girl will probably feel off colour for a day or two and may even be off her food, this is nothing to worry about and is perfectly normal. Obviously, she needs to get her appetite back as soon as possible so tempt her with bland foods like poached chicken, eggs or boiled rice.

These side effects shouldn’t last more than 24-48 hours, keep her under close observation and if you are anyway concerned, consult your vet for peace of mind.

Feeding A Pregnant Dog

How long is dog pregnancy?

Here’s the deal;

Dogs are pregnant for between 58-68 days, a lot shorter than human pregnancies and a lot happens during this relatively short period.


3 weeks

During the initial stages the fertilized egg divides from a single cell into 8 cells. This division continues until it reaches 16 cells and at this point the egg enters the uterus. Between 17-21 days this increases to 64 cells, and the embryo then embeds itself into the uterine wall. During this time, the placenta, which delivers oxygen and essential nutrients to the developing puppy is also formed.

4-6 weeks

The main development stage, during this time the embryo becomes a foetus with the organs, skeleton, circulatory and urinary system being formed along with the sensory organs, skin and eventually hair.

In week 4 the eyes, face and spinal cord are developing, and it is at this time the puppy is most susceptible to birth defects. The size of the embryo at this point is around 14-15 mm. Whiskers, toes and claws develop in the 5th week and now the foetus starts to become a recognisable dog. By the end of the 6th week, the puppy is developing skin pigment and will be approximately 40-45mm in length.

7-9 weeks

By now the all the organs are developed and this is the time for growth, the puppy gains weight and is ready to be born safely at the end of week eight.

What Worms Can Dogs Get?


Transmitted to dogs that ingest fleas either on their own body or by eating rodents and wildlife which have fleas or tapeworms. These hungry parasites take nutrients from the dog and are made up of tiny segments, which can often be seen in your furry friends poop or around the anus. They look like a sesame seed or grain of rice and it is these which contain the eggs

Many over-the counter treatments are not effective at destroying tapeworms – they need to contain praziquantel so, you will need to read the packet. Alternatively, consult your vet who will prescribe a treatment which works.


A large percentage of new-born puppies are born with roundworm larvae already in their tissues. They are contracted when in the mother’s uterus!

Roundworms can also be transferred via a mother’s milk to nursing puppies and once in the digestive track they can grow up to 5 inches long. Gross, right! Especially when you consider a female roundworm can produce 200,000 eggs a day. That’s a lot of worms!

Here’s the kicker; even if you think your pregnant bitch is roundworm-free, these pesky parasites can lay dormant in the tissues of adult dogs activating in the last stages of pregnancy; infesting the puppies.

Worming a pregnant female dog  has no effect on any encysted larvae, therefore it cannot prevent the worms transferring to her babies. Which is why no matter how careful you are, puppies are still likely to have worms.


Adult whipworms, as the name would imply; look like tiny pieces of thread, they reside in the cecum, which is at the beginning of the large intestine.

They lay fewer eggs than most parasites so are difficult to detect even stool samples may not reveal that your beloved pet has these pests. They can be common in kennel situations, so breeders need to particularly vigilant. As with all parasites weight loss is a symptom and a heavy infestation can be very serious for both the pregnant dog and her babies


These vampire-like worms attach themselves to the walls of the small intestine and feed on blood. Nasty things, they can be contracted by older dogs in contaminated soil, whilst pups usually get them via the migration of the larvae in the womb or like roundworms from the mother’s milk.

Hookworms are an extremely serious condition for new-born puppies, who become anaemic from the worm’s blood-sucking and if not treated it can be fatal.

Why You Should De-Worm?

Here are 3 essential reasons why you should de worm a pregnant canine;

Of course, the #1 reason your best friend should be worm-free is their health but there are some other considerations too


You may be surprised we’ve mentioned cash, but, when you think about it; an expectant bitch should be fed a high-quality, protein-rich diet, and she will naturally eat more to feed her offspring. However, if she has any internal parasites these will deprive her of essential nutrients.

This means no matter how much you spend on good quality food and supplements, she will not get what she needs, right when she needs it most and all the money you invest on those expensive bags of food, to give her the best, will be wasted.

Another money matter; presumably, if you are a breeder you will be charging for the pups, hoping to get the best possible price and no-one wants to pay top dollar for unhealthy looking pups, riddled with worms.

Passing on worms

As mentioned above, mothers can pass parasites on to their new-born puppies either whilst pregnant or when whelping. In some cases, for example roundworms even if the mother has been wormed, the puppies may still have them. So, the best bet is to worm the mother and then the pups when they reach 2 weeks of age then fortnightly until they are 3 months old.


Dog pregnancies are not always straight-forward, and should there be complications, your mum-to-be will go through a caesarean section or surgery much better if she is healthy. Hookworms especially, which can cause anaemia can cause serious problems should there be a problem during a dog’s pregnancy.

When to stop exercising a pregnant dog?

You should continue to walk your dog daily as they need regular exercise to maintain a good bill of health. However, you should not be playing strenuous games where the dog could do damage to themselves.

Also, be sure to monitor there weight once a week because a pregnant female is at a higher risk of obesity and being overweight can cause implications. Just make sure they are gaining the correct amount of weight and if they are gaining to much, adjust the amount of exercise accordingly.

Natural options for a pregnant canine

Now, more than ever dog-owners are turning to natural alternatives to conventional treatments and the same is true with dog worming products.

Click here (insert link) to see our reviews on the best natural dog wormers

However, it is essential to check the ingredients on natural dog de-wormers as some contain garlic and wormwood which are not recommended during pregnancy.

A safe natural alternative is Diatomaceous Earth, (IT MUST BE FOOD-GRADE) which can be fed daily and is effective against internal and external parasites. You can continue to use this all through her pregnancy with no adverse reaction and as it also promotes gut health it’s a win win!

So What Options Do You Have?

Ideally your pooch should be de-wormed before she becomes pregnant and good hygiene practiced, to ensure she doesn’t come into contact with dog faeces or soil where worm larvae may be lingering.

If she became pregnant accidentally this may not be possible and if this is the case, she should be wormed in the last 2-3 weeks of confinement.

You should always consult your vet for advice on when to worm, the proper dosage and recommended products especially if your four-legged friend has any ongoing medical conditions. The internet is a wonderful tool offering fantastic advice, much of it conflicting, but it is no substitute for professional knowledge.

Final Thoughts

Welcoming new life into the world is amazing, especially if it happens to be a cute litter of puppies. However, just like humans, doggie pregnancies can encounter problems, be stressful and there is lots you need to know.

We hope this article has helped with giving you information on a pooch pregnancy and worming a pregnant dog.

John Devlin

Husband, father and avid dog lover. Currently the proud owner of George a pedigree Golden Retriever that barely leaves my side. However, cute this sounds a little break from the dog hairs every now and then would be nice!

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