U.S. girls are starting their periods earlier and taking longer to reach regular menstrual cycles : Shots

Girls in the U.S. are starting their periods about six months earlier, on average, than they were in the 1950s and 1960s, and more are starting before age 9, which is considered very early, according to a large-scale study. New Research Published in this week’s journal JAMA Network Open.

“It’s important to educate parents, caregivers and care providers about this trend and prepare their children.” Dr. Shruti Mahalingaiah He is a co-author of the study and an assistant professor of environmental, reproductive and women’s health at the Harvard T.H. Chan School of Public Health.

“The younger you are, the more confusing it can be. There is still a lot of stigma and silence around it,” Mahalingaiah says.

The study was based on data collected from more than 71,000 women who enrolled through the Apple Research app on their iPhones, who were asked to recall when they started getting their first period. The researchers found that, on average, menarche began at 11.9 years old between 2000 and 2005, down from 12.5 years old between 1950 and 1969.

In addition, the proportion of girls who started menstruation before age 11 increased from 8.6% to 15.5%, and the proportion of girls who started menstruation before age 9 more than doubled.

The study found a trend toward earlier menstruation across all age groups, but it was more pronounced among girls from racial and ethnic minorities and low-income backgrounds.

The researchers say it’s important to understand changing menstrual patterns because they’re an important sign of health.

“The age at which a person begins menstruating is like a barometer of their overall condition.” Lauren HoughtonAssistant Professor of Epidemiology at Columbia University Commentary Accompanying new research.

The study also found that an increasing number of girls are taking longer to achieve a regular menstrual cycle. Irregular menstrual periods are associated with several health conditions, including polycystic ovarian syndrome (PCOS). Early menarche is also linked to several adverse health outcomes, including an increased risk of cardiovascular disease, obesity, miscarriage, and premature death. It is also associated with several cancers, including ovarian, endometrial, and breast cancer.

“Having your first period before age 12 increases your risk of developing breast cancer by 20 percent,” Houghton says.

“When you look at the population, it becomes a very significant public health issue,” Dr. Frank Biro Dr. Schneider is a clinician-researcher at Cincinnati Children’s Hospital Medical Center whose research focuses on pubertal changes and associated health risk factors.

Biro points to other studies that have found that girls around the world are developing their breast buds — usually the earliest sign of puberty — six to 12 months earlier than before. Combined with a declining age at menarche, she says, “we can expect to see an increase in new cases of breast cancer over the next 10 to 20 years.”

Why did this happen?

So what is behind the changes in menstruation and puberty timing?

“When you look for a cause or an explanation, it’s not just one thing. There are multiple contributing factors,” Houghton said.

For example, obesity is known to increase the risk of early puberty in girls, and childhood obesity rates are rising, but stress is also known to be a contributing factor, and the two may be intertwined, Houghton said.

“When stress levels are high, your cortisol and androgen hormones increase,” Houghton explains, “and your fat tissue converts those hormones into estrogen, which then signals your body to grow breasts.”” Changes in estrogen levels also signal your body to start menstruation.

Endocrine-disrupting chemicals, which are widespread in the environment, probably play a role too: for example, phthalates, a type of chemical commonly found in many cosmetics and personal care products, are known to interfere with hormones, and some air pollutants are also known to disrupt the endocrine system.

So what can concerned parents do?

Researchers say that helping children eat a healthy diet (including plenty of fruits and vegetables) may help reduce risk factors for early puberty and early menarche. Regular exercise is also important. Getting enough sleep can also help. Some research Later bedtimes and shorter sleep duration have been shown to lead to earlier puberty.

Mahalingaiah also wants parents to prepare themselves and their children for the fact that menstruation may come earlier than expected, so that they are mentally prepared when the time comes.

This story was edited by Jane Greenhalgh