Just like children, puppies go through different stages of physical and emotional growth, which tend to follow a general progression but can vary from dog to dog. Many U.S. owners notice phases of chewing, selective hearing, or nervousness — and some even describe their pups as having a "stubborn teenage" attitude!
Recent American research shows this common experience is rooted in real developmental changes. Puppies do undergo an adolescent phase linked to puberty, marked by behavioral shifts driven by hormones and brain maturation.
Research conducted at top universities has studied puppies between five and eight months old and gathered feedback from hundreds of puppy owners across the U.S. This combined approach provided valuable insight into puberty-related changes.
Typically, puppies hit adolescence around the start of sexual maturity, which differs based on breed size: small breeds may mature as early as four months, while larger breeds reach this phase closer to 12 months, generally between 5 and 8 months.
The teen phase usually concludes following spaying or neutering, which removes sex hormones influencing many of these behaviors. In the U.S., veterinarians often recommend waiting until puberty has passed before neutering to allow natural growth and development. For intact dogs, adolescence typically ends around one year old, though large breeds can experience an extended phase.
This stage emerges due to rising sex hormone levels affecting both emotions and physical growth — sometimes even leading to puppy acne. The brain’s development also plays a significant role: the prefrontal cortex, responsible for self-control and decision-making, matures more slowly than the emotional centers, leading to impulsive and heightened emotional reactions.
Almost all puppies undergo adolescence unless development is unusually delayed, but the intensity can vary widely. Some pups exhibit obvious teenage behaviors, while others show only subtle changes.
Common signs include decreased consistency in obeying commands, often selectively ignoring their owner while responding better to others. Puppies might appear more easily distracted, harder to train, and prone to testing limits. Behaviors also include impulsivity, shorter attention spans, and exaggerated emotional responses.
These behaviors align with findings from one of the largest longitudinal puppy studies in the U.S., which reported peaks in barking, poor recall, and jumping around the 12-month mark. Controlled American studies have also documented a temporary drop in trainability during adolescence.
Typically, spaying or neutering signals the end of adolescence. If left intact, how long it lasts depends largely on breed and individual growth, with larger breeds often experiencing a longer adolescent period.
With an understanding of the hormonal and neurological changes during puppy adolescence, American pet owners can better support their pups through this tricky stage, promoting responsible pet care and a strong owner-dog bond.