Dysmenorrhea is a common gynecological disorder characterized by frequent, painful, and severe cramps during menstruation from abnormal uterine contractions. It affects between 16% and 91% of females of reproductive age. Between 2% and 29% of them have symptoms severe enough to hamper their daily activity.
In a world-first epidemiological study, researchers in Taiwan from the China Medical University Hospital have shown that the risk of developing dysmenorrhea increases up to 33-fold for females exposed to long-term air pollutants like carbon oxides, nitrogen, and fine particulate matter.
The analysis used long-term data (from 2000 to 2013) on air quality and public health from national databases (Taiwan’s Longitudinal Health Insurance Database). The results reveal Taiwanese girls and women living in the most polluted areas faced a significantly higher risk of developing dysmenorrhea than their peers exposed to lower levels of pollutants.
There is no known cure for dysmenorrhea, but individuals could manage its symptoms with hormonal contraceptives and anti-inflammatory drugs.
Chung Y Hsu, a professor at the College of Medicine, China Medical University, Taichung, Taiwan, and one of the study authors, said:
Research has already shown that women who smoke or drink alcohol during their periods, or who are overweight, or have their first period very young, run a greater risk of dysmenorrhea. Women who have never been pregnant are likewise known to be at greater risk.
But here we demonstrate for the first time another important risk factor for developing dysmenorrhea: air quality, in particular long-term exposure to pollution. We don’t yet know the underlying mechanism, but emotional stress in women exposed to air pollutants, or higher average levels of the hormone-like prostaglandins in their body, might be part of the answer.
The Study
- The researchers analyzed anonymized health measures from 296,078 females (about 1.3% of the total population) between 16 and 55 years old.
- They exclusively sampled females without any recorded history of dysmenorrhea before 2000.
- They looked for a long-term association between dysmenorrhea risk and air quality by noting the average exposure to carbon monoxide (CO), nitric oxide (NO), nitrogen oxide (NOx), nitrogen dioxide (NO2), and fine particulate matter (‘PM2.5′) over the 13 years. They obtained the air pollution data from the ‘Taiwan Air Quality Monitoring Database’ of the Environmental Protection Administration.
The Results
- 4.2% of females in the studied sample were diagnosed with dysmenorrhea for the first time from 2000 to 2013.
- Women living in more urbanized areas, women with lower income, and younger women tended to have a higher risk of developing dysmenorrhea.
- The age- and year-specific risk (aka ‘hazard ratio’) of developing dysmenorrhea increased by 16.7 to 33.1-fold for females from the 25% of areas with the highest annual exposure to air pollutants, compared to those from the 25% with the lowest exposure.
- The greatest individual effect among the pollutants was that from long-term exposure to high PM2.5.
Prof Hsu concluded:
Our results demonstrate the major impact of the quality of air on human health in general, here specifically on the risk of dysmenorrhea in women and girls. This is a clear illustration of the need for actions by governmental agencies and citizens to reduce air pollution, to improve human health.
What causes dysmenorrhea other than air pollution? Hormonal imbalances or underlying gynecological conditions like endometriosis, pelvic inflammatory disease, tumors in the pelvic cavity, or ectopic pregnancy.
Symptoms include pain in the lower back, lower abdomen, legs, cramps, diarrhea, nausea, vomiting, headaches, fainting, weakness, and fatigue. They are often life-long and reduce the quality of life, and therefore impose a significant socioeconomic impact. For example, females with the condition may be temporarily unable to attend school, work, or engage in leisure activities.
Other studies have linked air pollution to blindness, mental health problems like dementia, anxiety, depression, and schizophrenia, higher COVID-19 death rates, a shorter life expectancy, reduced productivity, and so much more.
