The menstrual cycle is primarily regulated by hormonal signals between the brain and ovaries. Weather does not directly control menstruation, but extreme conditions can place physical stress on the body and affect sleep , hydration, physical activity, appetite and stress levels. These changes may, in turn, affect ovulation and the symptoms experienced around a period.
A period arriving a few days earlier or later than expected can be unsettling, particularly during a heatwave, a spell of heavy rain or a sudden change in routine.
The body’s stress response involves hormones such as cortisol, which can affect the hypothalamic-pituitary-ovarian (HPO) axis that regulates ovulation and menstruation. P.M. At the same time, sweating leads to fluid and electrolyte loss. Together with heat-related fatigue and disturbed sleep, these changes can make menstrual symptoms feel more intense . Dr. Gopinath recommends changing menstrual products regularly, wearing breathable cotton underwear and keeping the area clean and dry. Scented products that can irritate sensitive skin should be avoided. Cloth pads should be washed thoroughly and dried completely before reuse. A period that is slightly early or late after a period of heat, poor sleep or disrupted routine may not indicate an underlying disorder. But repeated irregularity should not be explained away as a weather-related effect. If such conditions are suspected, appropriate evaluation and treatment may be needed.
Sandhya Vasan, director and senior consultant, gynecology, SIMS Hospital, Chennai, says extreme weather can act as a physiological stressor. Gopinath, director of reproductive medicine, Kauvery Hospital, Vadapalani, Chennai, says heat causes blood vessels to dilate as the body attempts to lose heat.
If this hormonal signalling is disrupted, ovulation may be delayed, occur earlier or, in some cases, be skipped, resulting in a longer, shorter or irregular cycle. Conditions such as PMOS (previously PCOS) and thyroid disorders can cause irregular periods and abnormal ovulation independently of weather.
Dehydration and physical stress can also affect the timing of ovulation, potentially shifting the next period.
Pavithra Ramakrishnan, consultant, obstetrics, gynecology and reproductive medicine, Apollo Speciality Hospitals, OMR, Chennai, says some women may notice heavier or lighter bleeding, fatigue and headaches during extreme heat.
