We all know that boys and girls are actually born by genes, but you know that genes are hereditary. Genes are actually related to chromosomes. There are many genetic materials arranged in sequence in chromosomes. Genes are a bit like video tapes, in which all the characteristics of parents are recorded and subtly passed on to the next generation.
There is a folk saying that "old men are easy to have daughters", and male sperm does gradually decrease with age; On the other hand, the acidity and alkalinity of women's vagina has a great relationship with boys and girls: sperm with Y chromosome is more active in alkaline environment, while sperm with X chromosome is more active in acidic environment. With the increase of women's age, the alkaline secretion in the uterus will be lower and lower, which is more suitable for the survival of X chromosome and easy to have daughters.
For the sake of performing arts, stars usually get married and have children later. Most stars don't get married and have children before the age of 30, and many people have their first child after the age of 30. From this perspective, the chances of having a girl easily are really great.
Don't look at the stars. They are usually glamorous. In a few minutes, they can earn hundreds of thousands. In fact, they need to pay a lot off stage. They have to film during the day, make announcements at night, practice songs during the day and sing at night. They have already flown to Beijing in Sanya during the day, and the hardships are beyond ordinary people's understanding.
High-density working environment will inevitably cause mental stress and physical fatigue. Studies have shown that if men are nervous for a long time, the number of sperm will decrease; Women will produce a strong acidic environment, which is not conducive to the survival of Y sperm. According to this statement, it is reasonable for stars to have baby girls one after another.