It is best not to breed the dog when it is menstruating for the first time, because the dog’s reproductive organs are not fully developed at this time, and it is more likely to have dystocia. You should also pay attention to the dog’s hygiene, and it is best to wear clothes for the dog. Wear physiological pants, and pay attention to keeping the dog warm to prevent the dog from catching a cold; feed some light food in the diet, and supplement the dog with nutrients; the dog cannot take a bath or exercise strenuously during the menstrual period.