How many days can sperm survive in the uterus?

Some women rely on ovulation to prevent pregnancy, but in fact this method has a very high failure rate. In addition to the fact that women's ovulation period may vary slightly every month and is difficult to predict, another important reason is that it ignores the issue that male sperm has a certain survival time after leaving the body. If you don't know how many days sperm can survive in the uterus, not only will your contraception fail, but even if you want a baby, you won't be able to calculate the days. Many people will ask, how many days can sperm survive in the uterus?

Since the ovulation period of each woman is different and the time of sexual intercourse is not fixed, the sperm must wait for the egg to increase the chance of meeting. Therefore, the length of time sperm survives in the female reproductive tract is closely related to fertility.

Sperm residence time in the uterus:

Changes in the acidity and alkalinity of cervical mucus have a great impact on sperm penetration. When the pH is less than 6.5, sperm stops moving. At pH 7, it has slight penetration ability. At pH 7.5, the penetration ability is normal. At pH 8.2, the penetration ability is even stronger.

There is a lot of mucus blockage at the external opening of the cervix, which causes many sperm to be unable to penetrate and die outside. Cervical mucus is thick and tough just after menstruation; as ovulation approaches, the mucus becomes more abundant, clearer, and more stringy due to the increase of estrogen in the blood; during ovulation, the mucus is more abundant, clearer, and flows out, making it easier for sperm to penetrate.

Sperm penetrates cervical mucus by relying on the hydrolysis of enzymes. Trypsin-containing chymotrypsin and hyaluronidase can hydrolyze cervical mucus, reduce viscosity, and eliminate sticky thread formation, which is conducive to the passage of sperm.

Generally speaking, the survival time of sperm in the cervix is: inside the cervix, sperm can be found in the cervical mucus 15 minutes after sexual intercourse; one hour later, sperm enters the internal opening; inside the uterine cavity, sperm is found in the uterine cavity one hour after sexual intercourse, after 6 hours, all are active sperm, after 12 hours, 5/6 of the sperm are still alive, after 36 hours, 1/4 of the sperm are still alive, and after three days, there are no live sperm. But sometimes some individual sperm survive particularly long.

Knowing how long sperm can survive in the uterus, it will be much easier for female friends whether you want to use contraception or get pregnant. Therefore, if you are a woman who does not want to get pregnant for the time being, it is best to allow a few extra days when calculating the ovulation period and the dangerous period, and it is also best to take precautions three days before the ovulation period. Of course, for those who are planning to get pregnant, they can also act in advance to increase their chances.