After years of treating and resolving patients’ doubts, it is clear to me that the subject that generates the most errors and confusion is canine reproduction. We receive daily queries about spaying and neutering of females and males, whether it is harmful or beneficial and when it should be done.
The three most frequently asked questions about canine reproduction
Owners who are not sure how to prevent their dog from getting pregnant or how to care for her when she is pregnant. Some want to know if neutering their male dog will be effective in reducing his aggressiveness or dominance. Many are concerned that their dog got pregnant in the first heat and others want to know more about the estrous cycle of their male dog.
Therefore, I would like to clarify three of the most unknown and confusing points.
It is NOT true that a dog should breed once in her life.

Bringing a litter into the world is not a luxury for the dog nor does it have any health benefits, on the contrary, it involves a lot of effort and always has its risks. Especially since in most cases she is later separated from the puppies and therefore does not benefit from the mother-puppy relationship either. In any case, the owner will benefit from this if he sells them or, on the contrary, the puppies will end up paying dearly if nobody wants them and they end up being abandoned to their fate.
As far as their health is concerned, it is often damaged and in some cases for life. Dogs that become pregnant during the first heat, especially if they are large in size, have not yet completed their own growth and development, the dog is still a puppy and needs all the nutritional intake from her food to complete her growth correctly.
If she becomes pregnant, and with the subsequent lactation, she will be forced to “put aside” her own development to share nutrients between her and her puppies, and she will be at a disadvantage. In addition, problems often arise at birth (and/or spinal problems) due to incomplete bone growth. On the other hand, they are often not psychologically prepared to be mothers so, if the litter is successful, they do not always take care of their puppies properly, with the risks that this entails for their survival and enormous work for the breeder.
Birth control pills or injections are NOT preferable to spaying the dog.
I understand that it is not an easy decision and causes some fear to make your dog undergo surgery, but it is certainly the best option, with the current means, the risks and discomfort are minimal and not only avoid unwanted litters but also multiple uterine and ovarian pathologies and reduces the risk of mammary tumours.
On the other hand, hormonal contraceptive methods are less and less recommended by veterinarians and many of them have already been withdrawn, as it is being demonstrated that they predispose to some pathologies such as endometritis and uterine infections and there is an increasingly clear relationship with the appearance of mammary tumours.
Dogs do NOT have menopause or menstruation as such.
Dogs bleed during oestrus but, apart from being much less, this bleeding has a completely different meaning. In females this bleeding is due to the detachment of the endometrium as fertilisation has NOT taken place, therefore menstruation indicates in a certain way the END of the fertile period. In dogs it is diametrically opposite as the bleeding occurs as the BEGINNING of the fertile time.
The frequent comparison of dogs with humans gives rise to many errors, which in this particular area results in many scares in the form of unwanted pregnancies thinking that “as she has already bled” the oestrus was over, when in fact it was just beginning.
The same with regard to menopause, once again the humanisation of our pets leads us to believe that an older dog can no longer become pregnant. The dog continues to have cycles throughout her life, although it is true that due to certain pathologies or disorders there may be a distancing or even a disappearance of jealousy. It goes without saying that it is very harmful and totally inadvisable for an old or elderly dog to have to go through pregnancy.
Do you have any doubts? Consult our veterinary for Lenda VET Nature!
Illustrious College of Veterinarians of Lugo. Member number 1891
