The Declining Age of Menarche: Implications for Women’s Health Outcomes in the United States
- Yashesvi Sharma
- Jan 27
- 6 min read
It’s a Wednesday morning at an elementary school. Students bustle around the classroom – some giggling amongst themselves, others scribbling all over their homework pages, and some in argument with another over sharing crayons. Down the hall, a little girl is hunched over the toilet seat in the bathroom, eyes wide, wincing in pain, overwhelmed with fear and shame as she stares at blood on the toilet paper. While this may seem like the beginning of a coming-of-age film, it is unfortunately becoming a more and more common experience for young girls across the United States. The average age of menarche – one’s first menstrual cycle – is on a rapid decline, from 17 years of age in the 1890s, to 12 today, with some starting their periods as young as 8 years old. This article examines why menarcheal age is a significant health indicator, the major contributing factors to this phenomenon, and changes needed across public health and legislative fields to best support our most vulnerable.
The Menstrual Cycle
The menstrual cycle, which is typically 28 days long, can be broken down into four main components: menstrual phase, follicular phase, ovulation, and luteal phase. First is the menstrual phase (days 1-5) – where the endometrial cells (uterine lining) are shed, commonly known as period blood. During this phase, estrogen (female sex hormone) is low. Next is the follicular phase (days 6-13), where estrogen rises, and the uterine lining begins to form once again. During this time, the hypothalamus and pituitary glands are signaled to start ovulation. Third, ovulation (days 14-15), which is where the mature egg cell is released from the follicle. Estrogen is at its peak, and other hormones help to create a conducive environment for fertilization. Finally, the luteal phase prepares the uterus for implantation (when the egg is fertilized); if implantation does not occur, estrogen levels drop sharply, triggering menstruation. This cycle repeats every month, for on average, 35-40 years throughout one’s life, and recent research suggests that the timing of one starting menstruation may be a more significant health indicator than once thought.
Menarcheal Age as a Health Indicator
When an individual begins having periods at a younger age, their exposure to estrogen throughout their lifetime is much higher, since they will have more menstrual cycles. Estrogen’s primary role is to support the female reproductive system, by stimulating cell growth in breast, ovarian, and endometrial tissue. Earlier menarche creates more opportunities for DNA replication and mutation. In fact, according to the National Cancer Institute, in their article titled, “Age at Menarche Associated with Seven Cancers,” for breast cancer, starting a period before ages 11-12 carries a 15-20% higher risk compared to their counterparts who start menstruating after the age of 15. Furthermore, for endometrial cancer, each “earlier” year of menstruation increases risk by roughly 2%. Aside from cancer risk, shifting the window of puberty earlier in one’s life can alter baseline hormone levels, increasing one’s susceptibility to metabolic and cardiovascular disorders. Alternatively, in social contexts, early menarche is linked to higher stress, disproportionately so among marginalized groups. These groups also are more likely to turn to substance abuse, likely as a stress-response mechanism.
Increased Childhood Obesity Prevalence
It’s well known that the childhood obesity epidemic is rampant, but its impacts on health indicators, such as the age of menarche, are lesser known. According to National Public Radio (NPR), in their work titled “Girls are getting their first periods earlier. Here’s what parents should know”, obesity contributes to an earlier onset of menarche as a higher fat mass stimulates reproductive hormones (especially estrogen), telling the brain to begin puberty sooner, as stated by Lauren Houghton an assistant professor of epidemiology at Columbia University (2024). While obesity is a modifiable lifestyle factor, it’s vital to look at the broader picture. Most of the food widely available in the United States is high in calories, excess sugars, and fat, which contribute to the increased growth of fat cells in the body.
Renown Health, in their article “Early Onset of Puberty in Girls on the Rise”, includes an important point in this discussion: protein intake has been increasing nationwide. Increased animal protein intake elevates
IGF-1 (Insulin-like growth factor). IGF-1 provides insight into one’s growth stages; it is higher in adolescents to promote bone and tissue growth, and declines with age.
Adverse Childhood Experiences
Through a more social lens, adverse childhood experiences have been correlated with an average lower age of menarche. According to Sue Rochman, from Kaiser Permanente Division of Research, multiple studies revealed that girls with adverse childhood experiences were more likely to start their period before the age of 12 than their counterparts. Adverse childhood experiences include having imprisoned family members, emotional abuse, and domestic violence to name a few. This could be due to evolutionary biology, in which the body shifts its priorities to reproduction, rather than full emotional and physical development. This is a dangerous cycle, because those who start menstruating earlier are, overall, at increased risk for sexual abuse, and are more likely to experience depression, due to the social isolation behind maturing earlier than their peers. While the research is still hazy, these experiences impact individuals on a physiological level, altering stress-response pathways, and allowing puberty hormones to activate earlier.
Endocrine Disruptors in the Environment
Before discussing how exposure to endocrine disruptors increases one’s likelihood of early menarche, it’s important to understand what they are and how they physiologically impact the body. Endocrine disruptors are abundant in our environment – in plastics, hygiene and cosmetic products, and in some foods like soy. Examples of endocrine disruptors include Bisphenol A (BPA), parabens, phytoestrogens, and dioxins. They are absorbed into the bloodstream and either mimic or interfere with the body’s natural balance of hormones – including estrogen.
Despite their negative effects, there are legal challenges in regulating endocrine-disrupting chemicals – primarily because of their abundance. Because of this, it could provide difficulty for industries and research organizations to identify specific sources, further delaying legislative action. Additionally, since early menarche is a developmental problem, meaning that the condition presents itself after years of prolonged exposure, it is difficult to provide direct causation, which may be needed to move the needle on regulating the use of endocrine-disrupting chemicals in everyday items.
Implications for Future Generations
As previously discussed, early menarche is particularly harmful because it prolongs one’s exposure to estrogen, creating more opportunities for poor DNA replication and increasing the body’s vulnerability to environmental stimuli. In the United States, the age of menarche has been declining for centuries, and is expected to continue to do so, without government intervention. Globally, some experts say that the age of menarche will continue to decline, potentially reaching a biological limit, where menstruation would occur at baseline physiological possibility – with no regard for emotional maturity.
While genetics can play a role in one’s onset of puberty, it is vital to note that many of the contributing factors to premature menarche are modifiable, meaning that with lifestyle changes, this problem can be mitigated. However, it is the access to the solutions to these problems – living in areas further from industrial plants, access to nutritious food options, and having a high socioeconomic status – that creates the disparity. This is where the role of policy is vital: legislation can create access to these solutions through zoning laws, expanding eligibility for food distribution programs, and providing resources to those with adverse childhood experiences.
Looking to the Future
A region’s average age of menarche is not just an individual health marker, but can be indicative of a region’s wellbeing. Solving this problem starts with access. By creating opportunities for individuals, regardless of their socioeconomic status, to be involved in physical activity and have access to nutritious food, the first risk factor, high fat mass, has been addressed. In addition, working with schools and other institutions where children are most often found to provide resources for those with adverse childhood experiences could reduce their physiological and psychological burden. Next, making conscious, personal decisions to avoid endocrine disruptors in cosmetics, hygiene products, or food could help prevent early menarche. On a broader scale, creating and advocating for legislation to regulate the use of the most prominent endocrine disruptors and controlling the expansion of industrial plants into residential areas, could be an important step towards combating this phenomenon.
References
Age at Menarche Associated with Seven Cancers. (2021, September 10). Cancer.gov. https://dceg.cancer.gov/news-events/news/2021/menarche-seven cancers#:~:text=A%20study%20published%20in%20the%20journal%20*Cancer,Cancers%20of%20the%20colon%2C%20lung%2C%20and%20breast
Early Onset of Puberty in Girls on the Rise. (2018, July 5). Renown Health. Retrieved January 17, 2026, from https://www.renown.org/blog/early-onset-of-puberty-in-girls-on-the-rise
Godoy, M. (2024, May 31). Girls are getting their first periods earlier. Here’s what parents should know. NPR. https://www.npr.org/sections/shots-health-news/2024/05/31/nx-s1-4985074/girls-are-getting-their-first-periods-earlier-heres-what-parents-should-know
Overview of endocrine disruption | US EPA. (2025, December 2). US EPA.
Professional, C. C. M. (2025, December 8). Menstrual cycle. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/10132-menstrual-cycle
Rochman, S. (2025, July 1). Puberty in girls tied to adverse childhood experiences. Kaiser Permanente Division of Research. https://divisionofresearch.kaiserpermanente.org/puberty-tied-to-aces-in-girls/
Society, E. (2024, September 10). Girls may start puberty early due to chemical exposure. Endocrine Society. https://www.endocrine.org/news-and-advocacy/news-room/2024/girls-may-start-puberty-early-due-to-chemical-exposure
Society, E. (2025, July 13). Age at woman’s first period can offer clues about long-term health risks. Endocrine Society.
Sommer, M. (2013). Menarche: A Missing Indicator in Population Health from Low-Income Countries. Public Health Reports, 128(5), 399–401. https://doi.org/10.1177/003335491312800511
Weir, K. (2016, March 1). The risks of earlier puberty. American Psychological Association. Retrieved January 17, 2026, from https://www.apa.org/monitor/2016/03/puberty
Writer, S. (2025, June 4). Menstrual periods are arriving earlier for younger generations, especially among racial minority and. Harvard T.H. Chan School of Public Health. https://hsph.harvard.edu/news/menstrual-periods-are-arriving-earlier-for-younger-generations-especially -among-racial-minority-and-lower-income-individuals/
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