What are the stages of the formation of the fetus in the first month?

 The formation of the fetus in the first month


The formation of the fetus in the first month



The formation of the embryo in the fallopian tube begins the moment the sperm penetrates the wall of the egg and fertilizes it, as the fertilized egg begins to swim in the fallopian tube toward the uterus once fertilized. Reaching it soon,

 it begins by secreting a variety of hormones, and the uterine lining makes the necessary modifications to facilitate the attachment of the egg to the uterine wall and to stabilize the occurrence of pregnancy.


Fetal development stages in the first month

The formation of the fetus in the first month


  • The first cells are formed to form an embryo on the fourteenth day of the first day of the last menstruation after the sperm fertilizes the egg.
  • Once an egg is fertilized, it begins to divide, forming a small number of cells that are expertly differentiated into the various systems of the body.
  • The egg begins to travel from the fallopian tube to the uterus, during which time the cells feed on nutrients dissolved in the cellular fluid for only a few days.
  • The cells reach the uterus and feed from it with the help of uterine fluid.
  • The uterus begins to expand and then gradually expands to its size.
  • The cells of the fertilized egg continue to divide until they reach hundreds of cells.
  • On the tenth day of fertilization, the egg settles in the lining of the uterus, where it builds a nest, which means that the egg builds a nest for it in the uterus, where it begins to enter the uterus slowly to benefit from its, provide food and oxygen, and get rid of the waste it produces.
  • It appears that the umbilical cord has formed, and its blood vessels connect to the blood vessels of the fetus when they meet, and it is the only source of food and oxygen for the fetus during the remaining months of pregnancy, in addition to receiving waste from the fetus. fetus body.

In the third week, the fetus is round and covered with hundreds of hollow, fluid-filled cells, and some organs begin to develop, including the eyes and primary brain, as well as parts of the heart and nervous system.

In the fourth week, the hollow cells expand to become a small, disc-shaped, three-layered amniotic sac containing an array of living membranes.

At the end of the first month, the fetus's heart begins to beat, but the heartbeat cannot be heard because the heart is small and the pulse is narrow. The fetus is 1.25 cm long and weighs 28 g.