Intact female dogs (commonly called bitches) reach sexual maturity (puberty) between 4 to 18 months of age, at which time they experience their first estrus. There is a tremendous variability in the maturation age between breeds, and even within a breed of dog.

Several major phases compose the estrous cycle. Variations in the level of normal circulating hormones contribute to these different phases. Estrus – the period of breeding lasting approximately five to nine days; together with proestrus in known as the time of being “in heat”.

We recommend spaying non-breeding dogs before their first heat. Please call us if you have any questions or to schedule an appointment.