How many months does the fetus have?

After the sperm and egg combine, the fetus slowly begins to grow. In the initial stage, the fetus is just a test tube embryo. As the pregnancy cycle continues to increase, the test tube embryo gradually grows and becomes a baby with hands and feet. After a few months, you can also see the male reproductive organs through B-ultrasound. So, how many months does the fetus produce male testicles?

How many months does the fetus produce male testicles?

From the beginning of pregnancy, mothers have been wondering, is it a boy? Or a girl? This result can only be announced at the time of delivery. When does the difference between the gender of the fetus begin to appear in the womb? Generally speaking, when the fetus leaves the pregnant mother, we can roughly identify the gender of the baby based on the different appearance of its reproductive organs. Those with a "little penis" are boys, and those without one are naturally girls. In fact, when does the real difference between men and women begin to appear? Answer: It ends at the moment when the sperm and egg merge into a sperm-egg combination.

The test tube embryo has to go through a long 10 months (about 40 weeks) of division and development in the pregnant mother before it can come into the world. Under normal circumstances, when the embryo develops to 8-10 weeks, the male fetus will have testicles and begin to secrete testosterone. Testosterone causes the fetus's external reproductive organs to develop in the male direction. For fetuses without testicles, due to the lack of testosterone function, the reproductive organs naturally develop in the female direction.

1. When the baby is born, the reproductive organs have basically formed.

During puberty, the reproductive organs develop further and more rapidly. Boys will experience voice changes, Adam's apples and beards; girls will experience secondary sexual characteristics such as breast development, increasing body size and regular menstruation, and eventually grow into real men and women.

2. Factors that determine whether a man or a woman will have a baby

This starts with genetic material - genes. The reason why microorganisms can often be passed down from generation to generation and reproduce continuously is because they have genetic material. This genetic material is called "gene", and genetic genes are stored in the sex chromosomes of somatic cells. Sex chromosomes determine an individual's characteristics and hold the secret of whether a fetus can become a boy or a girl. Simply put, the sex chromosome karyotype determines whether the fetus has testicular development.

Each human reproductive cell contains 46 sex chromosomes, 23 of which come from the father and the other 23 from the mother. In other words, a child gets 50% of his genetic material from each parent.

Of the 46 sex chromosomes, only 2 play a fundamental role, so they are called "chromosomes." Men's chromosomes are XY and women's are XX. The fetus only gets the X chromosome from the mother, and can get the X chromosome or the Y chromosome from the father. If an X chromosome is obtained, the fetal chromosome karyotype will be 46,XX. Testicular development will not occur during the 8th week of IVF, and the baby will grow into a woman in the future. If the child gets a Y chromosome from the father, the sex chromosome type of the child will be 46, XY, and testicular development can occur in the 8th week of IVF.