It is a mystery to have boys and girls, but the mystery is not determined by fate, but by both men and women. The sex ratio at birth is generally 1:1 without artificial selection. At the beginning of the 2th century, scientists discovered the chromosomes in human cells, and only then did they uncover the mystery of sex. It turned out that the birth of boys and girls was determined by a pair of sex chromosomes in fertilized eggs. Every cell of human body (including germ cells) has 23 pairs of chromosomes carrying genetic materials, of which 22 pairs are autosomes, all the genes contained in 23 pairs of chromosomes are genetic information, and the other pair is a sex chromosome, which determines the sex of the fetus. The types of trait genes contained in autosomes are the same for men and women, with no gender difference. Sex chromosomes are different. A pair of male sex chromosomes consists of X chromosome and Y chromosome (the male chromosome set becomes 22+XY), and a pair of female sex chromosomes are all X chromosomes (the female chromosome set becomes 22+XX). Half of the 23 pairs of chromosomes come from the father and the other half from the mother. Human cells reproduce by meiosis, that is, one cell divides into two, and two cells divide into four, and so on. In the process of developing from immature germ cells to mature germ cells, the chromosomes in the cells undergo two divisions, and the last one is meiosis, that is, the mature sperm or egg cells only contain 23 chromosomes, which is half of the original, of which 22 are autosomes and 1 is sex chromosomes. One pair of male sex chromosomes is XY, so one kind of sperm containing X sex chromosome is called X sperm, and the other one containing Y sex chromosome is called Y sperm. A pair of female sex chromosomes is XX, so the eggs after division and maturity all contain one X sex chromosome. Therefore, there are two kinds of male sperm, while there is only one kind of female egg. Therefore, the birth of boys and girls depends on the types of male sperm cells.
The secret of having boys and girls
Although the formation of fetal sex has a certain relationship with sexual life, it still cannot completely determine the sex of the fetus. However, it is possible to improve the chances of choice. In order to understand the principle, let's start with the characteristics of sperm. According to the research, it is found that sperm X and sperm Y have their own characteristics. Sperm X has a larger head, larger volume, slower activity than sperm Y, stronger acid tolerance and penetration into cervical mucus than sperm Y, and longer life. Sperm Y head is small and round, and its volume is smaller, which moves faster than sperm X, but its tolerance to acidity and penetration of cervical mucus are weak, and its life span is short. The proportion of Y in semen with less sperm is low, and the proportion of Y in semen with more sperm is high. According to these characteristics, we can try to adjust the sex of the fetus through sexual measures.
Choose the time of sexual intercourse:
Those who want to have a boy have sexual intercourse (or insemination) during ovulation, that is, it is easy to have a boy, because sperm Y is weaker than sperm X when pregnant in October
, and can't wait as long as sperm X, and the closer the ovulation period is, the thinner the cervical mucus is, and the alkalescence is beneficial to sperm Y. On the contrary, those who want to have a daughter should be as far away from the ovulation period as possible. At this time, the more viscous the cervical mucus is, the more acidic it is, which is unfavorable to sperm Y and relatively tolerant to sperm X.
mastering orgasm:
during sexual intercourse, pay attention to regulating orgasm. Some people say: "Because your wife reached orgasm, she gave birth to a boy", which is well-founded. Because the vagina is acidic, when women reach orgasm, the mucus secreted by the cervix is alkaline. That is to say, the higher the degree of orgasm, the more alkaline secretion, and the easier it is for Y sperm to survive. On the contrary, if the man ejaculates before the woman reaches orgasm, some Y sperm will lose vitality because of the contact of semen with acidic secretions in the vagina, which may increase the chance of female fetus.
Number of times to control sexual life:
18-25 years old, 1-3 times a month, 25-35 years old, 5-15 times a month, 35-45 years old, 2-1 times a month. Normal people produce 3 million sperm every day. Excessive sexual intercourse can reduce sperm, so the proportion of sperm Y is low and the interval between sexual intercourse can be prolonged. If you want to have a daughter, there is no need to limit the interval of sexual intercourse.
Using diet to adjust the pH in the body:
According to foreign medical investigation data, men's semen is weakly alkaline, and their wives have more boys, which is because sperm Y is active and vigorous in alkaline environment; If it is weakly acidic, it will give birth to a girl, because the activity of sperm X increases in acidity. Therefore, if you want to have a boy, you should keep your body fluids weakly alkaline and eat more alkaline foods, such as fresh vegetables and fruits. If you want to have a girl, you should slightly acidify your body fluids and eat more acidic foods, such as rice, fish, meat and eggs. Because some foods taste sour, people mistakenly regard them as acidic foods, such as hawthorn, tomatoes, vinegar, etc. In fact, these things are typical alkaline foods.
Pay attention to the depth of sexual intercourse:
If the ejaculation position is shallow, it will take a long time for sperm to reach the uterus; On the contrary, the position of ejaculation is deep, and sperm can reach the uterus earlier. Therefore, if you want to have a boy, shoot semen into the deep vagina during sexual intercourse, which will help Y sperm to appear near the cervix and avoid the difficulty of its long journey through cervical mucus; If you want to have a daughter, shoot semen into the superficial vagina, which will intentionally increase the difficulty for Y sperm to cross long distances, so that X sperm will be far ahead and combine with eggs first. The above points are not absolute, but just a matter of how many opportunities there are. Having boys and girls should let nature take its course. For those who need to choose the sex of the fetus when one of the husband and wife is sick, it can be used as a reference to increase the chances of a fetus of a specific sex. However, in order to have a boy or a girl, it is not only completely unnecessary to do it deliberately, but it will hurt your body.