Overview
Menarche stands for the onset of menstruation. It marks a moment of sexual maturation in which the reproductive system is ready, following a series of physiological changes to support the new functions. When this experience occurs at or before the age of ten (some researchers establish it at twelve or before), it is called early menarche.
Although menarche is guided by genetic tendencies, it can be triggered by stressful events, obesity and a variety of other variables that might anticipate its occurrence. Early menarche raises vulnerability to teen pregnancy, besides influencing psychological and social development. Studies report it can be associated with a higher risk of breast cancer, type 2 diabetes and cardiovascular diseases in adulthood.1
Trends in early menarche
Historical perspective
The average age of menarche worldwide has decreased, especially over the last century. Overall, the first menstruation used to happen at around 17 years of age, and now, it is more common around 13 years of age. Even though genetics, quality and access to meals and social activities play a role in the age of menarche, the trend transcends socioeconomic status and ethnicity. Modern lifestyle and environmental changes have such a high impact on people's lives, that they may justify that tendency.2
Factors contributing to early menarche
A wide range of variables may influence the age of menarche. A few of the most common examples are listed and briefly described below:3
- Genetics
- Obesity: being overweight during childhood is associated with early menarche, especially if the child carries high fat levels in the period right before puberty (5 to 9 years of age)
- Nutrition: A high-calorie diet and high animal protein intake have been associated with early menarche
- Environmental factors: endocrine-disruptor chemicals (EDC) are substances commonly used in industrialised products (solvents/lubricants, plastics, pesticides, fungicides, pharmaceutical agents). Their molecular structure may resemble a few hormones, causing them to compete for receptors. When a hormone does not connect to its proper receptor, its function is compromised. It can cause metabolic alterations that can lead to early menarche
- Socioeconomic factors: early menarche is more common within urban residences than rural ones. A variety of other factors may affect the onset of menstruation like parental mood disorders, stressful family environment, etc
Long-term health risks and implications of early menarche
Cardiovascular risk and diabetes
The earlier the menarche, the higher the predisposition to high BMI, insulin resistance, and high blood pressure. All of these tendencies can increase the risk of cardiovascular diseases, stroke and diabetes.3,5
Polycystic ovary syndrome (PCOS)
The tendency to insulin resistance and obesity is probably why early menarche can be related to the later development of PCOS.6
Breast cancer
Early menarche has been reported to be a risk factor for breast cancer. The effects of it on multiple hormones like insulin, testosterone and growth factor, a test for its tendency to mammary tissue proliferation, which can lead to malignancies.3
Depression and anxiety
At the time of the first menstruation, puberty is already causing a variety of body alterations to reach a mature reproductive system. When this experience is happening precociously, the now pre-teenager may experience psychological disturbances and suffering. It commonly triggers body shame, self-objectification and poor sexual decisions. Early menarche is a risk factor for depression and anxiety.3
Anticipated menopause
Reports show that early menarche is a risk factor for both premature menopause (before the age of 40) and early menopause (between 40 and 44 years old).5
Early menarche and fertility
Age at menarche is not proven to have a direct influence on fertility, the natural reproductive capability. Early menarche has different meanings depending on the place, societal pressure, education status, and stressful environment. In practical terms, surroundings play a significant role in the outcomes.
An example is from a study by McKibben (2003), reporting on the relationship between age at menarche and fertility in Chinese women. Under the context of place, culture and time, a girl experiencing early menarche, in a society in which women usually marry in their mid-20s, is wasting good quality follicles in comparison to girls who have their menarche later.7
In general, experiencing an earlier onset of menstruation means that one can generate offspring earlier. It can result in psychological disturbances related to sexual life and insecurities about physical changes. Also, alterations in a few biological marks can be expected from that, like an earlier menopause.
When an individual first experiences menstruation, her body is mature enough to start releasing follicles, the “eggs” that are apt to be fertilized. The quantity of these follicles is finite within a body born with a functional female reproductive system.
It means that all the eggs released during life, through menstrual periods, are already stocked from birth. The longer they keep “in store”, the more they age and decay in quality. When menopause happens, the remaining follicles are no longer able to be fertilized.
Therefore, it is expected that the earlier the onset of menstruation, the earlier the peak in fertility compared to individuals with later menarches. Both people of the same age tend to hold different quality types of “eggs” depending on when they first had their period.8
Short-term fertility outcomes
- Potential early peak in fertility
- Shorter reproductive lifespan
Long-term fertility outcomes
- Higher risks of infertility in later life
- Impact on pregnancy outcomes
Psychosocial impact on reproductive choices
- Influence on the timing of first pregnancy: the earlier the reproductive system is functioning, the earlier a pregnancy is possible
- Potential for early menarche to impact family planning decisions
Summary
The moment of menarche is a hallmark for puberty and reproductive development. It symbolizes a physical maturity to start the transitional phase between childhood and adulthood. For some, it happens during their mid to late teenage years, but if the first menstrual period occurs at the age of 10 or earlier, it characterizes an early menarche.
At that age, it can be tougher to go through the hormonal changes of puberty than it already is for adolescents. It can trigger depression and anxiety in comparison with their peers who are yet to have their first period, but also because of insecurities related to body development and all the psychological implications of a menstrual cycle. Early menarche tends to cause an early initiation to sexual life.
The younger the individual, the more likely they are to make poor and dangerous decisions regarding that matter. An early matured reproductive system can follow a series of consequences that are not certain and depend on the individual experience and culture but show a higher tendency for teen pregnancy, decreased quality of follicles during mid-life, and earlier menopause, for example.
References
- Lacroix AE, Gondal H, Shumway KR, Langaker MD. Physiology, Menarche. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 [cited 2024 Aug 16]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK470216/.
- Ramraj B, Subramanian VM, G V. Study on age of menarche between generations and the factors associated with it. Clinical Epidemiology and Global Health [Internet]. 2021 [cited 2024 Aug 16]; 11:100758. Available from: https://www.sciencedirect.com/science/article/pii/S2213398421000622.
- Karapanou O, Papadimitriou A. Determinants of menarche. Reproductive Biology and Endocrinology [Internet]. 2010 [cited 2024 Aug 16]; 8(1):115. Available from: https://doi.org/10.1186/1477-7827-8-115.
- Soliman AT, Alaaraj N, Sanctis VD, Hamed N, Alyafei F, Ahmed S. Long-term health consequences of central precocious/early puberty (CPP) and treatment with Gn-RH analogue: a short update: Long term consequences of precocious puberty. Acta Biomedica Atenei Parmensis [Internet]. 2023 [cited 2024 Aug 16]; 94(6):e2023222–e2023222. Available from: https://mattioli1885journals.com/index.php/actabiomedica/article/view/15316.
- Carroll J, Saxena R, Welt CK. Environmental and genetic factors influence age at menarche in women with polycystic ovary syndrome. Journal of Pediatric Endocrinology and Metabolism [Internet]. 2012 [cited 2024 Aug 16]; 25(5–6):459–66. Available from: https://www.degruyter.com/document/doi/10.1515/jpem-2012-0047/html.
- McKibben SL, Poston DL. The influence of age at menarche on the fertility of Chinese women. Biodemography and Social Biology [Internet]. 2003 [cited 2024 Aug 16]; 50(3–4):222–37. Available from: http://www.tandfonline.com/doi/abs/10.1080/19485565.2003.9989073.
- Thiyagarajan DK, Basit H, Jeanmonod R. Physiology, Menstrual Cycle. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 [cited 2024 Aug 16]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK500020/.