Using Progesterone between Heat Cycles

Currently in most first world countries, the only approved progesterone compound for use on breeding bitches is one that inhibits the production of gonadotropin (FSH and LH) and is usually administered 32 consecutive days during the period of anestrus with a very low dose rate or, on the contrary, during eight consecutive days in the first days of proestrus, in a higher quantity; in fact, according to the manufacturers, megestrol acetate apparently hasn't produced any adverse effects on bitches treated with his product. The only secondary effects that have apparently shown up on our slight weight increase, a minor swelling of the breasts and certain apathy and indifference.

However, and this is the most curious part of this treatment, they are still extremely attractive for the males and even accepts the male; nevertheless, although there can be mating, pregnancy does not take place because the ovarization process has been blocked by the treatment.

We have seen that there are many secondary effects and risks that can come from using these heat control methods; in fact, the hormonal manipulation of heat cycles in females is advised against, and most responsible breeders are not willing to assume the risks that come along with the practice in exchange for punctually eliminating a heat cycle and they simply prefer to avoid, during risk days, any contact with males.