Age significantly impacts the canine reproduction capacity and health of both male and female dogs. In females, as they age, the frequency of estrus cycles may become irregular, leading to decreased fertility. Older females are also at higher risk of complications during pregnancy and birth, such as dystocia (difficult birth) and maternal health issues. On the other hand, older male dogs may experience a decline in sperm quality and quantity, which can affect fertility. Additionally, age-related conditions like prostate enlargement or infections can further impact reproductive health in males. Regular veterinary check-ups and appropriate breeding management are crucial as dogs age to mitigate these risks and ensure the health of both the breeding pair and offspring.