There is always blood in the nose in late pregnancy, clinically there are mainly the following reasons: First, the systemic hormone level of pregnant women in late pregnancy changes significantly, resulting in the expansion of the blood vessels in the nasal cavity as well as submucosa throughout the body, which easily induces nasal bleeding. Secondly, the systemic blood volume of pregnant women in late pregnancy increases significantly, causing the nasal vessels to dilate significantly and increasing the probability of bleeding. Thirdly, pregnant women may have elevated blood pressure in late pregnancy, which may cause them to bleed due to elevated blood pressure and easily induce some small blood vessel wall rupture. Fourth, pregnant women may lack some vitamins in the late stage of pregnancy, which may lead to the increase of brittleness of some capillary walls in the nasal cavity, thus inducing nasal bleeding. Fifth, in late pregnancy, pregnant women are more anxious, sleep not very well, easy to catch fire, etc., easy to dry and erosion of the nasal mucosa, thus inducing bleeding.