There are two causes of vulvar enlargement in late pregnancy, one is physiological and the other is pathological. Physiological vulvovaginal enlargement occurs in late pregnancy when the fetus increases in size and the uterus also increases in size, which can compress the inferior vena cava and lead to obstruction of return flow and vulvar enlargement. Especially in the second trimester, when the fetus is in the pelvis, it will increase the pressure on the vulva, resulting in the swelling. During this period, you should try not to stand for a long time and rest in bed to reduce the swelling of the vulva. There is also a situation when there is an inflammatory infection, the phenomenon of local redness and swelling of the vulva, accompanied by itching, you should try to pay attention to hygiene, pay attention to washing, wear loose cotton underwear, so as to avoid local skin stimulation, reduce the feeling of redness, pain and itching of the vulva.