pregnant dog nursing

Can Dogs Get Pregnant While Nursing? (Explained!)

Lactation is a common attribute of all mammals. The natural milk produced by the mother dogs helps to provide essential nutrients and transfer immunity to newborn puppies because puppies often have a weak immune system at birth.

The milk secreted by dogs in the first 24 hours after whelping is called colostrum and it is highly concentrated with nutrients, growth hormones, and antibodies.

During pregnancy, there is an increased production of prolactin and oxytocin, the hormones responsible for milk production and secretion, respectively. From about one day to one week before delivery, lactation begins lasting up to 10 weeks.

To understand whether dogs can get pregnant while nursing, a knowledge of the dog’s heat cycle will be required. Below we’ll give a detailed answer to that and discuss how long to wait for the next heat and pregnancy.

Can Female Dogs Get Pregnant While Nursing?

No, female dogs normally cannot get pregnant while nursing their pups because they are not in heat during this period. Dogs go in heat about 4 months after delivery but pups often nurse for 4 to 5 weeks after birth.

The knowledge of the canine heat cycle is needed to understand when dogs can get pregnant. The canine heat cycle is split into four phases the proestrus, estrus, diestrus, and anestrus phase.


Several physiological and behavioral changes occur during the proestrus stage of a dog’s heat cycle, which lasts for around 7 days. Swollen vulva and bloody vaginal discharge are frequent symptoms.

Bitches release different pheromones at this time of the heat cycle that males find attractive. Female dogs also frequently exhibit aggressive behavior but are receptive to males although they are not willing to mate.


When a female dog is in the estrus phase of the heat cycle, she is receptive to males and ready for mating and is said to be in heat or season. Dogs can experience estrus for two to three weeks. Despite not containing any blood, the vaginal discharge

In order to signal their openness to mate, female dogs in heat are often seen raising their tails forward and slightly to the side. If mounted by an unneutered male during this time, your dog may become pregnant.


If your dog does not get pregnant, this will be a resting period. It often lasts between two and three months. The vaginal discharge ends when the enlarged vulva returns to normal. It is accompanied by the fall of estrogen levels and the elevation of progesterone levels.


Anestrus lasts for three to four months and is characterized by decreased reproductive activity. During this time, the uterus and cervix repair in preparation for the next heat and possible pregnancy, thus either vaginal discharge or vulva swelling disappears.

How Long After Having Puppies Can Female Dog Get Pregnant

Dogs with an average heat cycle length — which is 6 months, can go into heat and become pregnant in about 4 months after whelping. You will have to wait through the anestrus and proestrus phases of the heat cycle before dogs can be in heat again.

The anestrus and proestrus phases of the heat cycle, as well as the length of the heat cycle, differ amongst dog breeds. While small dog breeds go through a shorter heat cycle, large dog breeds go through longer ones. Individual differences do exist, nevertheless.

Some physical and behavioral changes occur when a dog goes into heat. You can tell your dog is in or about to go into heat by looking for the following signs.

  • The dog’s vulva — the outer part of the dog’s reproductive system, becomes swollen and red.
  • The beginning of the canine heat cycle is marked by the presence of serosanguinous vaginal discharge which turns straw-colored during estrus.
  • You may notice excessive licking of the genital area in order to clean up the vaginal discharge.
  • Dogs in proestrus are seen tucking their tails between their legs or sitting down but tend to lift and flag their tails during estrus.
  • Dogs become receptive to males. They are often aggressive at first but become more open to mating when in heat.
  • Female dogs tend to urinate more often than not, leaving pheromones at different spots to alert males.
  • Male dogs are usually attracted to the cycling female.
  • Dogs in heat may become restless, nervous, or agitated.

Why Is My Dog Producing Milk When She Is Not Pregnant

Normally, dogs produce milk a few days before delivery, and this milk is used to nourish their young ones. There are other cases where dogs produce milk or a milky substance from their teats without pregnancy or delivery.

False Pregnancy

False pregnancy also known as pseudo pregnancy, describes a condition where there are various hormonal changes similar to those seen in true pregnancy but in this case, the dog is not pregnant. It occurs in unspayed dogs and the signs start at about six to eight weeks after the previous heat period.

Dogs with false pregnancy show signs of true pregnancy like mammary gland enlargement, lactation, restlessness, weakness, nesting, and display of motherly affection. If you suspect false pregnancy in your dog, you can ask your vet to run a pregnancy test.

Mammary Gland Tumors

Just like false pregnancy, mammary gland tumors are more common in unspayed dogs. In this condition, there is an abnormal multiplication of cells in the mammary glands. At times, this is accompanied by the production of a discharge. You can check for the presence of solid masses in the palpation.


Hypothyroid dogs have a low level of thyroxine (T4) in circulation commonly caused by inflammation of the thyroid gland or adipose cell infiltration of thyroid glands. This can affect cellular metabolic processes producing common signs like loss of coat, excessive shedding, weight gain, lethargy, infertility, and inappropriate lactation.

Can A Pregnant Dog Nurse Other Dog’s Puppies

A pregnant dog can nurse the pups of another mother dog but this will is not always recommended because the milk reserve of the nursing dog can be reduced leaving less-than-enough milk for the nourishment of her offspring.

Milk production begins a few days before delivery and the milk produced on the first day after whelping, known as colostrum, is usually important for the nutrition and immunity of your dog and should not be given to other dog’s puppies. However, there will be no issues if dogs nurse their litter for a while before accommodating a few extra pups.

In the case where dogs have very few puppies in a litter, feeding other dogs’ pups may not be problematic. There are also effective ways to boost milk production in nursing dogs like increasing their water intake, providing high-quality diets, and the use of special supplements.

How Long Does It Take A Female Dog To Recover From Having Puppies

Recovery begins immediately after birth and it usually takes about 5 to 8 weeks for your dog’s body to return to normalcy after various bodily changes that occurred during pregnancy.

During the recovery process, uterus tissue repair takes place, and the swollen abdomen and enlarged nipples gradually assume their normal size. Your dog may also shed extra weight caused by pregnancy. This recovery process can be longer, especially in larger dogs.

After pregnancy, dogs tend to be exhausted, lethargic, or show signs of loss of appetite. Dogs tend to recover faster from these conditions.

Make sure to keep an eye on the mother dog and the litter for any unusual symptoms and quickly seek medical attention in such situations. Providing a nutritious diet, good hygiene, and multivitamin supplements to the nursing dog is important for quick recovery.

How Many Puppies Can A Dog Nurse At Once

Dogs usually have 8 to 10 nipples and can nurse at once, as many as puppies as the number of their nipples. It is not always convenient for small dogs that can only nurse up to 6 pups as opposed to larger dogs than can nurse up to 13 puppies.

To improve lactation, breeders often offer the nursing dog high-quality formulas with high digestibility. Puppy food is often preferred for lactating dogs because it is high in calories, protein, vitamins, and minerals. The use of milk replacement and tube feeding for puppies is important if the dam can not produce sufficient milk to nourish her litter.

How Long After Birth Do Puppies Nurse

Puppies need to start nursing immediately after they are born because the first milk produced by the mother dog, known as colostrum, is densely packed with nutrients and antibodies for your dog’s nourishment and immunity.

You may need to assist them at first as they are not used to this method of feeding. If this does not work, try bottle-feeding them puppy formula.

Final Thoughts: Can Dogs Get Pregnant While Nursing

Lactation begins a few days before delivery and lasts for up to 10 weeks. During this period dogs are usually out of season, so there is a zero chance of dogs getting pregnant while still nursing their litter.

If you try to breed a female dog that is not in heat, pregnancy will not occur. However, male dogs do not have a heat cycle and can be bred at any time of the year.

In essence, you have to wait for the next heat for female dogs to be able to get pregnant. You can tell a bitch goes into heat by looking at various physical and behavioral changes like vulva enlargement, bloody vaginal discharge, receptiveness to males, excessive grooming, and urination.

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