Late periods, unusual fatigue, irritability, difficult nights, or more intense premenstrual syndrome... During heatwaves, many women feel like their menstrual cycle changes. But can heat really disrupt periods?
With the increasing frequency of heatwaves, this question comes up regularly. Some women report periods arriving earlier or later, while others experience certain menstrual symptoms more intensely.
So, is it just an impression, or a real effect of heat on our cycle?
Heatwave and periods: what does science actually say?
To date, there is no scientific evidence to confirm that a heatwave directly causes a delay or early arrival of periods.
A study published in 2024 in the scientific journal Cureus, conducted among 484 young women in Saudi Arabia, looked at the influence of weather conditions on various menstrual symptoms.
Participants were asked about:
- their pain;
- their fatigue;
- their bloating;
- their mood;
- their anxiety;
- their sleep disorders.
The results suggest that certain weather conditions could be associated with variations in the intensity of some symptoms.
However, researchers are cautious: this study does not demonstrate that heat directly advances or delays periods and does not establish a cause-and-effect link.
Why might our periods seem different when it's very hot?
The answer may primarily come from the indirect effects of heat on our body and daily life.
During a heatwave, we may experience:
- poorer quality sleep;
- more fatigue;
- dehydration;
- decreased appetite;
- dietary changes;
- different physical activity;
- greater physical stress.
However, several of these factors can influence the normal functioning of the menstrual cycle.
Stress, significant weight changes, certain dietary changes, or intense physical activity can notably be associated with irregular or delayed periods.
Heat would not necessarily be directly responsible for menstrual irregularities: it could rather create conditions likely to temporarily disrupt our balance.
Our body temperature also changes during the cycle
Our body doesn't regulate its temperature in exactly the same way during all phases of the menstrual cycle.
After ovulation, mainly due to progesterone, body temperature naturally rises slightly.
This is one of the reasons why basal body temperature can be used to monitor the cycle and ovulation.
When this phase of the cycle coincides with a period of intense heat, the sensation of thermal discomfort can be greater for some women.
More difficult nights, fatigue, or a constant feeling of being too hot can then be added to the usual cycle symptoms.
Can a heatwave make premenstrual syndrome harder to bear?
Fatigue, irritability, sleep disturbances, bloating, or discomfort can already accompany premenstrual syndrome.
When it's over 30°C, these symptoms can combine with the classic effects of heat.
This doesn't mean that the heatwave causes premenstrual syndrome, but rather that some women may experience this period more intensely when their body also has to manage significant heat.
However, every woman is different: our cycle, our sensitivity to heat, and our symptoms are never exactly the same.
How to better manage your period during a heatwave?
A few simple gestures can improve your comfort.
💧 Hydrate regularly
During hot weather, our body loses more water.
Drink regularly throughout the day and don't necessarily wait until you are very thirsty to hydrate.
🌙 Take care of your sleep
Hot nights can be particularly difficult during your period.
Close your shutters during the hottest hours, ventilate when the outdoor temperature drops, and opt for light clothing to sleep in.
🥗 Continue to eat enough
Heat can reduce appetite.
However, your body still needs energy and nutrients, especially during a time when you might already feel more tired. Find our article on foods to eat during your period
🩸 Choose comfortable menstrual protection
When it's hot, the comfort of menstrual protection becomes even more important.
Choose protection suited to your flow and daily life, and change it according to usage recommendations or if you feel the need.
Sherydane menstrual panties are designed in Switzerland and made in France, notably from GOTS-certified organic cotton and OEKO-TEX® Standard 100 certified materials.
They can replace or complement classic menstrual protection depending on the chosen model, flow, and needs of each woman.
→ Discover Sherydane menstrual panties
What if you want to swim during your period?
Heatwave often rhymes with swimming pool, lake, sea, and holidays.
And having your period shouldn't force you to give up swimming.
Sherydane menstrual swimsuits directly incorporate menstrual protection suitable for swimming.
They can notably allow you to continue enjoying the pool, beach, or lake during your period, without necessarily having to use internal protection.
→ Discover our menstrual swimsuits
Late periods during a heatwave: beware of quick conclusions
If your period is a few days late during a heatwave, don't automatically conclude that the heatwave is responsible.
A delayed or absent period can have many causes:
- pregnancy;
- stress;
- significant weight change;
- intense physical activity;
- hormonal contraception;
- certain hormonal disorders or health problems.
If pregnancy is possible, a test may be indicated.
And if your cycles become unusually irregular, if changes persist over several cycles, or if you notice unusual pain, bleeding, or symptoms, seek advice from a healthcare professional.
So, does heat really disrupt periods?
What we currently know:
☀️ High heat can make certain phases of the cycle more uncomfortable.
💧 A heatwave can change our sleep, hydration, diet, or physical activity.
🩸 These changes could indirectly contribute to certain cycle variations in some women.
🔬 On the other hand, science does not currently confirm that heat directly causes a delay or early arrival of periods.
Our cycle does not function independently of the rest of our body. Sleep, stress, diet, hormones, physical activity, and environment are closely linked.
So during hot weather, one rule remains essential: listen to your body and adapt your rhythm to your needs.
Experience your period differently with Sherydane
From first periods to different moments in a woman's life, Sherydane develops reusable menstrual protection designed to combine comfort, material safety, and environmental respect.
🇨🇭 Swiss design
🇫🇷 French manufacturing
🌿 GOTS-certified organic cotton
✓ OEKO-TEX® Standard 100 certified materials
→ Discover Sherydane and our menstrual protection
- Alqahtani et al., Effects of Weather on the Severity of Menstrual Symptoms Among College- and High School-Going Women in the Southern Regions of Saudi Arabia, Cureus, 2024.
- General information regarding late or missed periods: NHS.
This article provides general information and does not replace the advice of a doctor or other healthcare professional.
