Sperm survival time in the fallopian tube is within 72 hours. After ovulation sex sperm will be in a few minutes to half an hour time, can pass through the cervix, the uterine cavity to reach the fallopian tube, in 72 hours to meet the egg can be combined to develop into a fertilized egg, more than this time sperm may be dead, and can not be combined with the egg, and therefore can not lead to pregnancy. If a woman wants to get pregnant and have children, it is best to have intercourse on the day of ovulation and a few days before and after the day of ovulation to have a higher chance of getting pregnant, but at the rest of the time, since no egg is discharged, even if there is a sperm that survives, it will not lead to pregnancy. Normal intrauterine pregnancy in women occurs not only when the egg and sperm are able to combine and then reach the uterine cavity to settle and grow and develop, but also with the environment of the uterine cavity and the nutritional status of the whole body has a great deal to do with.