The menstruation of female dogs usually lasts for 7-16 days, and some dogs may even last for 20 days. When a dog menstruates, it means that it has entered estrus. At this time, the owner can breed it. Generally, the breeding success rate is the highest on the 11th day of menstruation. If the dog has more menstruation, the owner can also breed it. It wears menstrual pants to prevent walls and floors from getting stained.

If the owner does not want to breed the dog, and does not plan to let the dog have children in the future, then he can choose to sterilize, but he must wait until the dog has finished menstruation, otherwise it will easily cause genital bleeding. It is generally recommended to perform neutering surgery one week after the dog's menstruation, which is most appropriate.

Dogs usually have their first menstrual period at 6-7 months of age, but some dogs may delay it until 8 months of age. Although they enter estrus at this time, they are not suitable for breeding. , because it has not matured physically, pregnancy will increase the burden on the genitals, resulting in residual damage.