Dogs Health Cards N° 19.The sterilization of the dog



Sterilization will not only eliminate any risk of unwanted reproduction but also avoid the disadvantages associated with heat in the dog (blood loss, behavior change, assaults of male dogs ...).

Other advantages are associated with ovariectomy, especially since surgery is performed early.


Ovariectomy involves removing both ovaries from a female dog.

It requires general anesthesia.

Your pet will usually be kept at the clinic for a day: you will be asked to bring your pet in the morning on an empty stomach. The intervention will be practiced in the morning and your bitch will be returned to you, well awake, in the evening.

Two techniques can be used:

- The ovariectomy by the white line (the scar of the intervention will be at the level of the belly of the animal)

- Ovariectomy by the flanks (the veterinarian using in this case access to the abdomen by the flanks of the animal)

The veterinarian will practice one or the other of these techniques according to his / her preferences.


- Heat suppression:

The ovariectomy will make it possible to make disappear the periods of heat and the blood losses which accompany them. It should be noted that in a non-sterilized dog, sexual cycles are present throughout the life of the animal (there is no menopause in the dog).

- In a household with several dogs:

Sterilization may have an interest in the management of certain behavioral disorders particularly in homes where several dogs cohabit:

The hormonal cycle modifies the perception of the status of an animal within the pack, giving rise to situations of confrontation and competition between the different females. Sterilization (and therefore the suppression of heat) allows a more harmonious cohabitation and limits the cases of aggressiveness between bitches.

In case of hereditary disease

Sterilization prevents the reproduction of animals suffering from hereditary diseases.

Preventive role in several pathologies

- Ovariectomy limits the risk of uterine infection.

- It also prevents the appearance of any ovarian tumor since the ovaries are removed during the procedure.

- Some bitches tend to make lactations of pseudo-gestation (or nervous pregnancies): they behave then as if they waited for small and secrete even milk. This disorder tends to be repeated in some females after each period of heat.

The ovariectomy prevents the recurrence of these "nervous pregnancies" (the surgical intervention can be practiced after the medical treatment to stop the lactation)

The operation is all the more interesting because repeated lactations of pseudo-gestation and poorly treated favor the appearance of breast tumors.

- Finally, numerous studies have shown that the sterilization of a young female dog greatly reduces the risk of developing breast tumors later. Knowing that mammary tumors represent one of the most frequent cancers in dogs, this advantage is not negligible.


The ideal age for the sterilization of a dog is before its first heat (heat usually starts around 6 months in small breeds, around 12 or even 18 months in giant breeds). Your veterinarian will tell you the best time to perform the procedure.

The prevention of mammary tumors is maximal when the dog is sterilized before its first heat (when no hormonal impregnation of the breasts has yet taken place)

The benefit of the intervention then gradually decreases as the dog ages:

- The risk of developing breast tumors is 0.05% in a sterilized bitch before its first heat compared to a non sterilized bitch

- It is 8% in a dog sterilized between its first and its second heat

- Then 26% after the second heat

- Over 36 months, there was no decrease in tumor risk compared with the risk of developing a breast tumor in a non-sterilized female.


Sterilization of the dog may have some disadvantages:

- Some animals will tend to gain weight after surgery.

- A small number of bitches may develop a so-called "castration" incontinence (especially bitches of certain large breeds such as Boxer, Bobtail, Rottweiler or Dobermann)

Suitable solutions exist for each of these disadvantages:

- Your veterinarian will advise you as to the feed to give to a sterilized animal in order to avoid any weight gain after the operation.

- Most castration incontinence responds well to medical treatment.

Do not hesitate to ask your veterinarian all the questions concerning the points that could worry you to be perfectly reassured before the intervention.

If the sterilization of the dog may present possible disadvantages, they are much less in comparison with the benefits of the intervention.


Even in an older female who has not been sterilized, ovariectomy (removal of the ovaries) or ovariohysterectomy (excision of the ovaries and uterus) may become necessary for medical reasons:

- In case of affections of the uterus an ovariohysterectomy must be practiced:

This is the case for congenital uterine abnormalities, uterine tumors, polyps, uterine hemorrhage, pyometra (uterine infection), but also for torsion or uterine rupture.

- In breast tumors:

In some breast cancers, breast tissue is rich in hormone receptors. The hormonal variations linked to the heat will then tend to increase the rate of development of the cancer or to lead to recurrences even after withdrawal of the mammary masses.

In these cases, sterilizing the animal in addition to the removal of the tumor will greatly decrease the risk of recurrence and greatly increase the life expectancy of the dog (these dogs then have an average survival time of 45% Superior to those of non-sterilized bitches)

- Finally, the ovariectomy can indirectly help better manage certain pathologies:

During endocrine disease (eg diabetes), every hormonal change related to the dog's cycle tends to interfere with the medical treatments received by the animal. The sterilization of the dog will make it possible to eliminate these disadvantages and thus to better treat the disease.

The sterilization of the dog has therefore many interests. The benefits brought by the intervention are all the more interesting because the operation is performed in a young dog.

The ideal age for sterilization is shortly before the animal's first heat.