Researchers indicate that obesity and the impact of environmental chemicals may play a significant role in the increasingly early and irregular menstrual cycles observed in women compared to previous generations.
According to the Washington Post, a new study involving 71,341 women highlights growing concerns as the age at which girls begin menstruating is decreasing. This trend is even more pronounced among certain racial and ethnic groups.
Early and Irregular Menstrual Cycles
The findings also reveal that many young girls and women have been experiencing irregular menstrual cycles for several years, a risk factor for various health issues including cardiovascular diseases, metabolic disorders like diabetes, and certain types of cancer.
The data was collected as part of the Apple Women’s Health Study, developed by the Harvard T.H. Chan School of Public Health in collaboration with the National Institute of Environmental Health Sciences (NIEHS) and Apple.
The age at which girls begin menstruating is decreasing – (Photo: NYT).
The study utilized cycle tracking data from iPhones and Apple watches, along with surveys to gather more information about menstrual cycles, health risks, and gynecological conditions. These findings may not represent the entire U.S. population.
However, these results, published in JAMA Network Open, reflect other studies, including those examining menstrual age trends among white and Black women in the U.S. over the last 50 years, based on data from the National Health and Nutrition Examination Survey, a government report on health trends.
The new study in JAMA indicates that the average age of first menstruation among Apple users has decreased to 11.9 years for those born between 2000 and 2005, compared to 12.5 years for those born between 1950 and 1969.
Participants who identified as Asian, non-Hispanic Black, or multiracial consistently reported an earlier average age of first menstruation compared to white participants.
The researchers emphasized that this data is crucial, as Hispanic and Asian groups have not been extensively studied in previous research on the age of first menstruation. The study also introduced the concept of “vital sign” – the timeframe between the first menstrual cycle and the establishment of regular cycles.
Early Menstruation Leads to Increased Health Risks
Zifan Wang, the lead researcher and a postdoctoral fellow at Harvard T.H. Chan School of Public Health, stated: “We found that children have a longer time for their menstrual cycles to become regular. This is concerning because irregular menstruation is an important indicator of potential adverse health events later in life. It serves as a warning sign. We need to provide earlier counseling and intervention for irregular cycles in children and adolescents.”
The data also indicated that the proportion of girls starting menstruation before age 11, or very early menstruation before age 9, is predominantly found among those born more recently compared to older cohorts.
Shruthi Mahalingaiah, one of the study’s authors and an assistant professor of environmental health, reproductive health, and women’s health at Harvard T.H. Chan School of Public Health, noted that girls who begin menstruating at a very young age may face more significant health challenges throughout their lives.
Mahalingaiah emphasized that early onset can signal future health conditions, assisting doctors in making care decisions. She highlighted that a healthy diet, regular exercise, and adequate sleep are crucial for girls of all ages.
She remarked: “I would reiterate the importance of awareness and education for parents and healthcare providers. We need to consider health-enhancing factors we can implement to impact not only the age of menstruation but also the time it takes to achieve regular cycles.”
What is Happening?
According to researchers, obesity in children is a risk factor for early puberty and appears to contribute to this trend. However, the earlier age of first menstruation has been observed even prior to the obesity epidemic, indicating that other factors are at play.
A significant concern is “forever chemicals”, with nearly 15,000 synthetic chemicals used in various consumer products found in many food sources and water. These endocrine-disrupting chemicals, along with heavy metals and air pollutants, may play a critical role in early puberty.
Moreover, poor dietary habits, including high sugar intake, stress, and adverse childhood experiences, may also affect the timing of puberty.
