Why do people have menstruation?
Menstruation is a natural phenomenon of cyclic changes in the female reproductive system and an important symbol of human reproduction. Although menstruation has been with women for decades, many still question the biology behind it. This article will combine recent hot topics and scientific data to analyze the causes of menstruation from three dimensions: physiological mechanism, evolutionary significance and social discussion.
1. The physiological mechanism of menstruation
The menstrual cycle is precisely regulated by the hypothalamic-pituitary-ovarian axis and is divided into the following four phases:
| stage | duration | Main features | Hormone changes |
|---|---|---|---|
| menstrual period | 3-7 days | Endometrial shedding | Lowest levels of estrogen and progesterone |
| follicular phase | 7-10 days | follicle development | estrogen gradually rises |
| Ovulation period | 24-48 hours | egg release | LH hormone peak |
| Luteal phase | 10-14 days | corpus luteum formation | Progesterone Dominant |
When fertilization does not occur, the degeneration of the corpus luteum causes hormone levels to plummet, causing endometrial vasoconstriction, tissue necrosis and shedding, and the discharge of menstrual blood. A recent study in the journal Nature pointed out that endometrial stem cells can rapidly regenerate after each cycle. This repair ability is a unique biological characteristic of humans.
2. Explanation from an evolutionary perspective
In 2023, the Harvard University evolutionary biology team proposed the "uterine defense hypothesis" and sparked heated discussions:
| theory | core ideas | evidence support |
|---|---|---|
| embryo screening theory | Periodic shedding clears implantation of low-quality embryos | Comparative study of primates |
| Pathogen removal theory | Discharge menstrual blood and take away intrauterine pathogens | Menstrual blood immune cell analysis |
| energy distribution theory | Avoid continued endometrial depletion | Basal metabolic rate calculation |
It is worth noting that under the topic #MenstruationEvolution# on social media recently, popular science blogger @bioticmiao pointed out: "Human menstrual flow is 3-5 times that of other primates, which is related to changes in pelvic bone structure caused by walking upright." This view received 120,000 likes.
3. New social and cultural hot spots
Based on the analysis of network data in the past 10 days, menstruation-related topics show the following trends:
| platform | Hot search topics | focus of discussion | Participation |
|---|---|---|---|
| #Menstrual Poverty Solution# | Hygiene products tax exemption policy | 320 million reads | |
| Tik Tok | "Menstrual cycle calculation method" | Popular science about natural contraception | 85 million views |
| Zhihu | "Why menstruation is contagious" | Pheromone Effect Controversy | 4200 answers |
It is worth noting that under the topic of Xiaohongshu #Menstruation Art Exhibition, the performance art created by young artists using menstrual blood has triggered polarized discussions, reflecting the diversified development of society's understanding of menstruation.
4. New discoveries in modern medicine
The latest research data from The Lancet in 2024 shows:
| research project | sample size | Key findings |
|---|---|---|
| Menstrual cycle and immunity | 56,000 women | Luteal phase vaccine response efficiency increased by 17% |
| menstrual migraine | 12,000 patients | Estrogen fluctuations are the main trigger |
| Menarche age trends | global data | 50 years ahead of schedule by 1.5 years (improved nutrition) |
Experts remind that the "menstrual detoxification theory" recently circulated on the Internet lacks scientific basis. The components of menstrual blood are mainly endometrial fragments, blood and vaginal secretions, which have nothing to do with the liver detoxification mechanism.
Conclusion
As a unique phenomenon of human reproductive biology, menstruation not only guarantees the continuation of life, but also reflects the progress of social civilization. Understanding its essence can help eliminate "menstrual shame" and promote the development of women's health. As the World Health Organization's 2024 report emphasizes: "Menstrual health is an important indicator to measure social equity," which requires the joint advancement of scientific understanding and social support.
check the details
check the details
en
