Human immunodeficiency virus (HIV) infection
In 1994, someone wrote a review on the relationship between circumcision through epidemiological surveys and the risk of HIV infection. At that time, there were 30 relevant survey results, including 26 cross-regional surveys, 18 surveys from 6 countries that showed that they had a clear relationship in statistics, 4 surveys from 4 countries that showed this trend, and 4 surveys from 2 countries that showed no relationship, There are also two forward-looking and ecological surveys that show a clear relationship. Since then, the author has approved another 11 cross-regional and 5 prospective surveys. Among these 11 cross-regional surveys, 8 survey results show that there is a clear statistical relationship between the presence of foreskin and HIV infection. One thinks there is a trend, one thinks there is no relationship between the two, and the other thinks that circumcision will increase the risk of HIV infection. As far as we know, the last survey is the only one that holds this view, that is, circumcision will increase the possibility of HIV infection after excluding other potentially uncertain factors.
Different sexual experiences or health habits make the relationship between circumcision and HIV infection vague. For example, those who routinely undergo circumcision may have different sexual behaviors from those who do not undergo circumcision. Therefore, the difference in the risk of HIV infection may be due to differences in sexual behaviors rather than whether circumcision is necessary. A study in Uganda showed that although the health habits of circumcised and non-circumcised men are no different, both men and women feel it is difficult to keep the non-circumcised male genitals clean. How to explain the relationship between genital hygiene and HIV infection and other genital infections needs further research.
In most epidemiological observations, circumcision can reduce the probability of HIV infection by 2-3 times, but in fact it may decrease more.
Sexually transmitted diseases (STD)
The relationship between foreskin and sexually transmitted diseases other than HIV infection is complex and varies with the individual's sexually transmitted diseases. At least 11 surveys have fully demonstrated the relationship between the lack of circumcision and ulcerative sexually transmitted diseases (especially chancre and syphilis). So far, no statistically significant investigation has been found, which indicates that circumcision increases the risk of sexually transmitted diseases or that there is no relationship between the two. For genital herpes, two surveys showed that there was a statistically significant relationship with the lack of circumcision, and four showed no relationship. For gonorrhea, 5 items are related and 2 items are irrelevant. For chlamydia, non-gonococcal or other types of urethritis, 2 items showed correlation, and 3 items showed negative correlation. For genital warts, there are 1 related, 1 irrelevant and 1 negative correlation. In addition, there are also investigations that the absence of circumcision will lead to the presence of anaerobic bacteria, G (-) bacilli, streptococcus and mycoplasma, which may be transmitted to women, leading to bacterial vaginosis syndrome. Although these findings are not completely consistent, the relationship between the lack of circumcision and chancroid, syphilis, genital herpes and gonorrhea is confirmed, but the relationship between non-gonococcal urethritis and genital warts and circumcision is not conclusive.
Carcinoma of penis
In a review of the expert group on circumcision of the American Academy of Pediatrics in 1989, five major investigations on penile cancer from North America confirmed that all men with penile cancer did not undergo circumcision in the neonatal period (circumcision after the neonatal period may have no obvious effect on prevention of circumcision). There are similar reports in Africa. Men without circumcision may have increased sensitivity to penile cancer due to human papillomavirus (HPV). A recent survey in North America found that there was a significant relationship between penile cancer and non-circumcision in the neonatal period. A cross-regional survey in France found that the proliferation of neoplastic cells (PIN) in the epithelium of the penis was a precursor of penile cancer for some men, and was also related to the lack of circumcision. Although the debate has risen to the point that improving sanitation will reduce the risk of penis cancer, there is no scientific evidence for this. In the United States, it is estimated that about 750 to 1000 people suffer from penile cancer every year, almost all of which occur in men who are not circumcised after birth, with a mortality rate of up to 25%. Circumcision for newborns can reduce the incidence of penis cancer by at least 10 times, but there is still controversy on this point of view. That is, since most cases occur in men over 50 years of age, and the incidence rate of the disease is very low (about 2/100000 per year among men not circumcised in North America), circumcision for newborns cannot be the only effective measure to prevent penis cancer.
(Intern editor: Cai Junyi)