The Qing Palace Chart, also known as the Qing Palace Collection of Boys and Girls Chart, is a chart popular among Chinese people for predicting the gender of unborn babies. This kind of chart is said to be compiled based on the ancient Chinese theory of yin-yang and five elements and calendar knowledge, but in fact it has no scientific basis. 
The usage of Qing palace pictures is usually as follows:
1. Determine the mother\’s lunar age: First, you need to know the mother\’s lunar age when she was pregnant. Since China traditionally uses the lunar calendar, the age here refers to the age calculated according to the lunar calendar, not the Gregorian calendar (solar calendar) age.
2. Determine the lunar month of conception: Secondly, you need to know the lunar month of conception. Again, this refers to lunar months, not Gregorian months.
3. Find the intersection: In the Qing palace diagram, the horizontal axis represents the mother\’s lunar age, and the vertical axis represents the lunar month of conception. The predicted gender of the baby is obtained by finding the intersection of the row for the mother\’s lunar age and the column for the lunar month of conception.
For example, if a mother becomes pregnant in the lunar year when she is 28 years old, and the conception occurs in March of the lunar calendar, then find the intersection of the 28-year-old row and the March column on the Qing Palace Diagram, and the point corresponding to If the mark is \”male\”, it is predicted that a boy will be born; if it is \”female\”, it is predicted that a girl will be born.
It should be noted that the Qing Palace Map is just a folk superstition, and its prediction results have no scientific basis and should not be overly relied on. In modern science, the most accurate way to establish the sex of a fetus is based on ultrasound, which is usually more effective in the second trimester. In the process of preparing for pregnancy and pregnancy, we must pay more attention to the health of mothers and babies and follow the professional guidance of doctors.
As shown in the figure below, we can see that the horizontal coordinate is the month of pregnancy of the pregnant woman. Note that it must be calculated according to the lunar calendar. The vertical coordinate is the age of the pregnant woman. Then according to her actual age and the month of pregnancy, It is predicted that the child will be a boy or a girl.
1. If you are 24 years old in the lunar calendar, you will be pregnant with a boy in the third month of the lunar calendar, and you will be pregnant with a girl in the fifth month of the lunar calendar;
2. If you are 25 years old in the fictitious calendar, you will be pregnant with a boy in the third month of the lunar calendar. If you are pregnant in the seventh month of the lunar calendar, you will be pregnant with a girl;
3. If you are 26 years old in the lunar calendar, you will be pregnant with a boy in the sixth month of the lunar calendar, and you will be pregnant with a girl in the seventh month of the lunar calendar;
4. If you are 27 years old in the lunar calendar, you will be pregnant with a boy in the second month of the lunar calendar. Pregnancy in the sixth month of the lunar calendar will give birth to a girl;
5. If you are 28 years old, you will expect a boy in the fourth month of the lunar calendar, and you will expect a girl in the fifth month of the lunar calendar.
Does it depend on the man to have a boy or girl?
Being a boy or a girl does depend on the man, more specifically, it is determined by the sperm provided by the man. The human sex determination mechanism is the XY chromosome system. Women have two X chromosomes (XX), while men have one X and one Y chromosome (XY).
During fertilization, the female always contributes an X chromosome, while the male can contribute either an X or a Y chromosome. If the sperm carries the X chromosome and combines with the egg, then the fertilized egg will have an XX combination and develop into a baby girl; if the sperm carries the Y chromosome and combine with the egg, then the fertilized egg will have an XY combination and develop into a boy.
Therefore, the male’s sperm determines the gender of the child. However, although we know which chromosome determines sex, there is currently no reliable way to control the ratio of X and Y sperm in each ejaculate, or their relative motility and speed, to ensure the birth of a child of a specific gender.
In some special cases, such as when certain genetic diseases only affect children of a specific gender, assisted reproductive technology (such as PGD/PGS) can be used to select gender, but this is usually done in medical Conducted under necessary circumstances and subject to strict ethical and legal restrictions. In most cases, the birth of a boy or girl is a natural process that is not under human control.
