Tan beds and sunbathing may be associated with an increased risk of endometriosis

According to a new study, tanning beds and sunbathing not only increase the likelihood of women developing malignant melanoma, the most dangerous form of skin cancer, but they may also increase the risk of developing endometriosis. There is.

Over 116,000 studies Female Published today in the United States Human reproduction, One of the world’s leading reproductive medicine journals, Endometriosis Increased more young woman second hand Tan bed, From teens to young adulthood, sunburned and used sunscreen.

However, the study also found that women living in parts of countries with high levels of UV radiation throughout the year, such as the southern United States, are less likely to be diagnosed with painful conditions in tissues similar to the lining. It was. Part of the uterus begins to grow elsewhere, such as the ovaries and fallopian tubes.

Professor Leslie Farland, an assistant professor at the University of Arizona School of Public Health (USA), who led the study, said: “Previous studies on the long-term health effects of endometriosis suggest that women with endometriosis are at greater risk. Melanoma Endometriosis and melanoma association The exact mechanism underlying the disease is unknown, but some studies have shown that women are at increased risk of endometriosis, such as sun-sensitive, sun-resistant, red hair, bright eyes, and freckles. The number of uterus is high. These associations are the general genetic background between endometriosis and melanoma, or the underlying risk between exposure to sunlight and the risk of endometriosis. It may reflect relevance. “

Harvard TH Chan School of Public Health at Michigan State University Human Medicine University (USA), and Professor Farland and his colleagues at the French National Institute of Health Sciences (INSERM), Paris Saclay University, Birjuif (France), began in 1989 at the age of 25. We studied 116,429 women who participated in the American Nurse Health Study II at the age of 42. Until June 2015, every two years, participants completed a questionnaire asking about their medical history and exposure to risk factors for some chronic illnesses. When they participated in the study in 1989, participants were asked about their tendency to tan, the number of moles on their feet, and the number of their severe tans between the ages of 15 and 20. In 1993 they provided information on the use of sunscreens and in 2005 they reported on their use. Sunburn Beds for teens to early adults, and 25-35 years old.

Since 1993, participants have also been asked if they have endometriosis and have been diagnosed by laparoscopy. This is the gold standard for a correct diagnosis of the condition. Their home address was updated every two years and linked to the area’s annual ambient UV A and UV B data.

The researchers excluded women who reported endometriosis or who were diagnosed with cancer (including nonmelanoma skin cancer) when they participated in the study. They also limited the analysis to Caucasian women, taking into account the known racial and ethnic disparities in the diagnosis of endometriosis and the differences in the effects of UVA and UVB light on different races.

Of the 95,080 women included in the analysis, there were 4,791 cases of endometriosis diagnosed with laparoscopy during the follow-up period.

After adjusting the analysis to take into account factors that may affect results, researchers found that six times a year in teens and young adults compared to women who had never used a tanning bed. We found that 19% of the women who used it increased the risk of endometriosis. Using more than 6 times a year between the ages of 25 and 35 increased the risk by 24%, and using a tanning bed more than 3 times a year throughout life increased by 30%. Increased risk of endometriosis.

This is about 5 out of 100 women in utero over an average follow-up period of about 14 years per person if they have never used a tanning bed between teens, young adults, or between the ages of 25 and 35. It means that you can develop endometriosis, but nearly 7 women will develop it in 100 if they use a tanning bed more than 3 times a year.

Having a history of 5 or more sunburns between the ages of 15 and 20 increased the risk of endometriosis by 12% compared to women who had never had a sunburn. People who have always used sunscreen have a 10% increased risk of endometriosis compared to those who have never used sunscreen, which researchers used as an indicator of how long they participated in sunbathing and other outdoor recreational activities. Did. The absolute risk of developing endometriosis in women who tan more than five times a year between the ages of 15 and 20 was too small to show the difference between the two groups.

Women at birth, 15 and 30 years old, who lived in the sunny areas of the country, were at 19 risk of endometriosis, respectively, compared to women who lived in the areas with the least annual sunshine in the United States. It decreased by%, 21%, and 10%. This means that 4 in 100 women can develop endometriosis if they live in some of the countries with the highest UV levels at the age of 15.

Professor Stacy Mismer, a professor at Michigan State University’s College of Human Medicine, a professor at Harvard University’s School of Public Health, and co-author of the study, said: “Little is known about how to modify behavior to mitigate risk. Onset of endometriosis. Much remains about the relationship between recreational and residential sun exposure and the risk of endometriosis. We don’t know, but our findings suggest that avoiding excessive recreational sun exposure and sunbeds can reduce the risk of endometriosis. “

Endometriosis is estimated to affect about 10% of women. This is the first prospective study on the association between sun exposure and endometriosis, and researchers say further research is needed on other situations and findings with other groups of women. ..

“In the last three decades, more people have been diagnosed with skin cancer than all other cancers combined,” said Professor Farland. “From a public health perspective, we already know that women should avoid tanning beds to reduce the risk of melanoma. This study strengthens advice on avoiding tanning beds and the uterus. It suggests that there may be additional benefits of reducing the risk of endometriosis. Follow health advice and do not use a tanning bed. Prevent sunburn, cover up, look for shade, and extensive Use UVA / UVB sunscreen to protect your skin from exposure to the sun. “

The mechanism between exposure to sunlight and sunburn beds and the risk of endometriosis is unclear, and studies are observational, so it cannot be shown that these exposures cause an increased risk of endometriosis. .. The authors found that high-intensity exposure to UV is associated with a risk of DNA damage, cell damage, inflammation, and melanoma, especially tanning beds that primarily emit UVA light, which increases the risk of cell damage. It points out that it is related. The immune response weakens. All of these are associated with the risk of endometriosis. In contrast, when a woman lives in a more sunny area of ​​the world, she is exposed to more UVB light and stimulates the production of vitamin D in her skin. Vitamin D has been shown to suppress inflammation and boost immunity.

Other limitations of the study include that women may not remember themselves Hit the sun Exactly, especially when they were young. Some people were diagnosed with endometriosis before reporting their recreational exposure in 2005. Women in Nurse Health Study II are not a random sample of women in the United States. Since the researchers’ analysis was limited to white women, it may not be possible to estimate results for women of other skin tones or ethnicities.

Editor-in-chief Human reproduction, Dr. Nils Lambalk, Department of Reproductive Medicine, University of Amsterdam Medical Center, Vrije Universiteit Amsterdam (Amsterdam, The Netherlands) commented: “This study sheds some interesting light on the link between UV exposure and endometriosis. Further research can be done. FemaleHave a self-image and endometriosis. For example, if you are suffering from endometriosis, does this encourage you to look for ways to feel and look “better” or “healthy” through sunburn? Or are women who are not happy with their appearance more likely to have endometriosis? ”