Why does bleeding occur when the fertilized egg implants?

Some women will experience bleeding after the embryo implants. In fact, if the embryo implants normally, there will be no bleeding. However, because everyone's physical fitness is different, it cannot be generalized. So what is the cause of embryo implantation bleeding? What are the causes of bleeding? Regarding this issue, let's discuss the following detailed introduction.

What is embryo implantation bleeding?

The sperm and egg absorb nutrients and oxygen from the fluid secreted in the fallopian tubes and continue cell division. At the same time, the sperm and egg combine and slowly move toward the uterine cavity. When it arrives in the uterine cavity 3-4 days later, it has grown into a solid thread with multiple cells, which looks like a mulberry, so it is called a morula. The morula continues to divide in the uterus to produce a blastocyst, which enters the uterine wall about 6-8 days after fertilization. This process is called embryo implantation or implantation.

How many days will the bleeding last after the embryo implants? Generally speaking, the bleeding will last for a few days after the embryo implants, but the time is not likely to be too long. Eight days after ovulation and implantation, you may develop light pink or dark brown stains, and cramps may accompany these conditions. In fact, during the menstrual period, there may be some spotting and bleeding, but this is not a true menstrual period. It is the result of the fusion of sperm and egg and the implantation of the embryo in the uterine wall. The bleeding time after embryo implantation is similar to the normal menstrual period, and will not exceed 10 days at most.

The cause of implantation bleeding is that after the egg is fertilized and implanted in the early stage of pregnancy, the embryo cannot produce sufficient female hormones and estrogen; the ovaries are no longer active; and the uterine wall (decidua) attached to the embryo and covering the surface of the embryo is not completely combined with the true decidua on the surface of the uterus that is not in direct contact with the embryo. There is a cavity, so the uterine wall can still fall off, resulting in "menarche".