Staphyloma occurs in women of childbearing age, with the youngest reported to be 14 years old and the oldest up to 56 years old. The cause of the occurrence of gravida is not well understood, but studies have shown that the following factors may have some relationship with the occurrence of gravida. 1, racial factors: Since staphyloma is mostly seen in Asian countries, it is thought that it may be related to race. The incidence of staphylococcal pregnancy in Japan is about one per 1000 pregnancies, about three times higher than the incidence in Europe and the United States. The epidemiological survey in China found that the average incidence of gravida is 1:1290, with the highest being 1:728 in Jiangxi and the lowest being 1:3506 in Shanxi. in addition, the incidence of gravida is higher in Zhuang and Mongolian women than in Han Chinese women. 2, nutritional factors: according to the geographical distribution of staph, it is mostly seen in rice eating countries, and some people think it may be related to the eating habits of the residents. For example, rice is boiled in water for a long time and later the rice soup is poured away, which destroys and loses a lot of protein and vitamins. In addition, studies have shown that the lack of carotenoids and animal fats in the diet also leads to an increase in the incidence of staphylococytes. Therefore, women in areas with a high incidence of staphyloma can use dietary supplements of carotene, vitamin A and animal fat to prevent the occurrence of staphyloma. 3, infection factors: some scholars believe that the occurrence of staphylococytes is related to viral infection. The actual relationship between them is not yet clear. The incidence of hypertrophy increases exponentially when a pregnant woman is older than 35 years old, and is seven times higher than that of the general population when she is older than 40 years old, so it is thought that the occurrence of hypertrophy is related to the decline of ovarian function, and that the eggs may not be easily eliminated naturally after aging for abnormal fertilization. The first of these is the removal of the ovaries in the early stages of pregnancy, which can cause blister-like changes in the placenta, and thus it is believed that estrogen deficiency may be one of the factors that induce gravidity. 5, genetic factors: normal pregnancy cytogenetic examination are 46 chromosomes (i.e. diploidy), of which 23 from the father and 23 from the mother. In contrast, genetic examination of gravida cells revealed that although the vast majority of complete gravida were 46 chromosomes, they all came from the father, with no maternal component; partial gravida, on the other hand, all showed 69 chromosomes (i.e., triploidy), of which 46 came from the father and 23 from the mother. This suggests that an excess of paternal chromosomal components may contribute to the abnormal proliferation of placental villi and lead to the development of staphylocytosis.