According to the relative position of the uterine body and the longitudinal axis of the body, the position of the uterus can be classified as anterior, median and posterior. Posterior uterus can be classified into Ⅰ, Ⅱ and Ⅲ degrees according to the degree of posterior tilt of the uterus. Ⅰ and Ⅱ degrees are mostly asymptomatic and do not require special treatment, while posterior uterus of Ⅲ degrees can cause symptoms such as lumbar pain, anal cramping sensation and menstrual pain due to backward pressure of the uterus. The most common position of the uterus is anterior, and there are also some women with congenital uterus in a posterior position. As shown in the diagram, when the uterus is anteriorly positioned, the cervix is positioned backwards. When lying on the back, the lowest point of the vagina is the posterior fornix, and semen will accumulate in the position of the posterior vaginal fornix, and the cervical opening is positioned backwards to facilitate the entry of sperm into the uterine cavity. However, during ovulation, the secretion of cervical mucus reaches its peak and the degree of lacrimation can reach 10 cm, which can help sperm to swim into the cervix and uterine cavity. Therefore, if there is no combination of other gynecological diseases, normal ovulation, patent fallopian tubes and normal endometrium, a simple posterior uterus will not affect conception much and will not lead to infertility. In some patients, the posterior uterus is not congenital but caused by certain diseases, such as endometriosis and pelvic inflammatory diseases, which can cause serious adhesions in the pelvic cavity, causing the uterus to be stretched and cause deviation in position. In this case, the causes of infertility are mostly inflammation and adhesions in the pelvic cavity leading to ovulation disorders and tubal incompetence, as well as endometritis leading to a decrease in the tolerance of the endometrium. Therefore, there is no need to worry about a simple posterior uterus affecting pregnancy, but if you have been trying to conceive for more than 1 year and still have not conceived, you need to consult a fertility center to check for other factors affecting pregnancy.