It is a relatively normal phenomenon for dogs to return blood, but it is still somewhat inaccurate to identify whether they are pregnant. Many dogs will bleed after breeding. If you want to judge whether you are pregnant, you still have to judge based on changes in physical signs, such as changes in breasts and nipples, and ultrasound examination.

If there is still bleeding after half a month of breeding, and the blood is darker in color, detailed examination is needed to determine whether there are signs of miscarriage.

Signs of pregnancy in female dogs appear about one week after mating. The specific manifestations are that the vagina of a pregnant female dog will shrink rapidly, and pregnancy reactions such as vomiting and loss of appetite may occur at three or four weeks of pregnancy. At 20-30 days of pregnancy, the mammary glands of pregnant dogs will protrude, the breasts will swell, and the nipples will turn pink. In the fourth week after breeding, touch the location of the uterus on the female dog's abdomen with your hands. The pregnant female dog can feel an embryo as big as an egg.