Overwhelmed, irritable, dizzy, bloated, exhausted—these descriptors, submitted by women to the BBC as they brace for another heatwave after barely recovering from June’s record-breaking temperatures, underscore a phenomenon that medical experts argue is disproportionatelydisproportionately/ˌdɪsprəˈpɔːrʃənətli/L3不成比例地；过大或过小地to an extent that is too large or too small in relation to something else; in a way that is not balanced or fair severe for females. Dr Nighat Arif, an NHS GP specialising in women’s health, characterises heatwaves as a “stress-test” for the female cardiovascular system, while Dr Cat Pinho-Gomes, an academic public health consultant at UCL’s Institute for Global Health, notes that women may face marginally elevated mortality risks during extreme heat, though further evidence is required. As climate change intensifies the frequency and severity of heatwaves across the UK, researchers are advocating for heightened awareness of these gendered vulnerabilities and for targeted protective measures.
Biologically, the disparity hinges on two interrelated factors: hormonal fluctuations and divergent thermoregulatorythermoregulatory/ˌθɜːrmoʊˈreɡjələtɔːri/L3体温调节的relating to the biological processes that maintain a stable internal body temperature responses. Research, including a 2025 study, indicates that women produce less sweat and commence perspiring at a higher temperature, impairing their capacity to dissipate excess heat and obscuring physiological warning signs, given the lack of visible moisture on skin or clothing. Furthermore, women exhibit a higher core body temperature and greater body fat percentage, which functions as an insulating layer. Concurrently, the natural oscillation of oestrogen and progesterone—particularly pronounced during the menstrual cycle, perimenopause, menopause, pregnancy, and lactation—destabilises the brain’s temperature regulation, placing additional strain on the cardiovascular system.
Socioeconomic circumstances exacerbate biological predispositions, as Dr Pinho-Gomes emphasises in her review of sex differences in heatwave-associated deaths. Women, who on average earn less and disproportionately serve as primary caregivers, often possess diminished capacity to safeguard themselves during extreme heat. Age compounds this risk: longevity, which is greater among women, correlates with increased vulnerability to heat-related morbidity, particularly when compounded by dementia—which impairs thirst recognition—or by diuretic medications prescribed for hypertension. Consequently, the intersection of biology and socioeconomic disadvantage creates a compounded jeopardyjeopardy/ˈdʒepərdi/L3危险；风险danger of being harmed, lost, or destroyed; a state of serious risk that demands systemic attention.
Specific life stages amplify these effects. During the menstrual cycle, rising progesterone before menstruation elevates core temperature, while the subsequent drop in oestrogen—the hormone driving thermoregulation—forces the heart to work harder to cool the body. Michaela Finn, from north London, reported increased fatigue, dizziness, anxiety, and sleeplessness during her period in the June heatwave, noting that blood loss depletes iron, compromising oxygen delivery and further taxing the cardiovascular system. For perimenopausal and menopausal women, declining oestrogen exacerbatesexacerbates/ɪɡˈzæsərbeɪts/L3加剧；使恶化makes a problem, bad situation, or negative feeling worse or more severe hot flushes and night sweats, which global warming may intensify, as Hilary Serif, 57, from Cheshire, described as a “double whammy” that HRT mitigates but cannot eliminate.
Pregnancy imposes additional cardiovascular burden due to increased metabolic heat and fluid requirements, with fluctuating progesterone initially raising temperature before oestrogen stabilises it later in gestation. Jess Bloom, 35, expecting a baby in late July, characterised the experience as “hell,” resorting to sleeping on the kitchen floor and nightly cold baths. Dr Arif advises recognising signs of heat exhaustion and heat stroke, consuming fluids, utilising fans, exercising before sunrise or after sunset, and tracking menstrual cycles. She urges employers and policymakers to be “more mindful” of women’s sensitivity, while Dr Pinho-Gomes calls for greater female representation in decision-making roles, concluding that addressing these vulnerabilities is not merely a woman’s issue but a societal imperativeimperative/ɪmˈperətɪv/L3必要的事；紧迫的需要something that is extremely important and must be done without delay; a necessity or obligation.
