What happens after the fertilization of the egg?
In most cases, women do not feel when fertilization occurs in their bodies. Sensations (signs of pregnancy) appear, as a rule, after implantation. And first the process of the birth of a new life looks like this. The fertilized egg starts to move to the uterus, while continuing to divide and double the number of cells. In medicine, it is customary to call this egg morula after three days after fertilization, when its interior is filled with liquid and consists of 32 cells. That is, the morula looks like a raspberry, a berry consisting of small grains. Three days the egg moves into the uterus cavity, then the same time it moves to the place of implantation (attachment to the uterus). Now the morula turns into a blastocyst (from the Greek word blastos - embryo), consisting of 250 cells. Blastocyst is a trophoblast (villous surface) and an embryoblast (embryo of a future baby). The size of the blastocyst is 0, 15 mm. By the time of entering the uterus, the size of the blastocyst increases to 0.23 mm.
How does implantation occur?
The process of introducing a blastocyst into the soft wall of the uterus is called implantation of the fetal egg. It occurs on the seventh day after fertilization. How does this happen? Vorsinki trophoblast help penetrate the epithelium of the uterus and merge with the blood vessels of the mother's body. The implantation time is usually about 40 hours. Sometimes in the process of introducing an egg, there may be scarce bleeding - the only sign that signals a woman about the occuring attachment of the egg.
That is, according to time, implantation occurs 3-4 days after sexual intercourse. From this time, the development of a special hormone begins, which appears in the body of a woman only during pregnancy. It is called chorionic gonadotropin (hCG). It is on this hormone that pregnancy tests respond.
About the symptoms of implantation
Usually women want to know, are there any other symptoms of implantation and how to determine if it has taken place? Not all women can have even scant excretions at the time when the egg is attached to the uterus (4-7 days of unprotected intercourse). Sometimes these discharges can even be confused with the symptoms of other phenomena. For example, tumors of the uterus, endometriosis.
Other internal sensations, pains, changes in state of health, as a rule, while not. After all, the implantation process occurs at the cellular level, and there are no sensations when introducing the egg into the endometrium of the uterus. But to see a tiny germ the future mother can only on ultrasound at the beginning of the first trimester of pregnancy.
All rules have their exceptions. And they are also in the process of implantation. It is an ectopic pregnancy, when the fetal egg is attached not to the endometrium of the uterus, but to the fallopian tube. Then the pregnancy ends with a self-abortion. To identify this pregnancy and prevent possible consequences (rupture of the uterine tube), you need to turn in time to the gynecologist and become registered in the women's consultation.
Sometimes a fetal egg can be empty, and implantation occurs according to the usual pattern. In this case, pregnancy does not develop.
It is worth remembering about such a possible moment: if the implantation occurs during late ovulation, that is, after 16-20 days of the cycle, then the embryo on ultrasound can be seen much later.