A cat can become pregnant and give birth as early as 6 months old.
This is due to the fact that female cats (queens) can enter their first heat cycle as early as four months of age, although it's more common around 5-9 months. Because queens experience estrus cycles every 2 to 3 weeks during the breeding season (typically spring through early fall), they can become pregnant relatively quickly once they reach sexual maturity. A cat's gestation period is approximately 63-65 days. Therefore, a cat who becomes pregnant at 4-5 months could potentially give birth at 6 months old. However, pregnancy this early in a cat's life is not recommended due to health risks for both the mother and kittens.
