Breathe Better: Your Lungs & Your Cycle

You probably do not think much about your breathing unless something feels off. But if you have ever noticed that your workouts feel harder in the week before your period, or that you seem to breathe more shallowly when you are anxious and premenstrual, your hormones may be playing a bigger role than you realise.

The lungs are not exempt from the hormonal shifts of your menstrual cycle. Estrogen, progesterone, and even cortisol have measurable effects on how your respiratory system functions, how deeply you breathe, how sensitive your airways are, and how much oxygen your working muscles can access. For most women, these changes go unnoticed. But for women with asthma, anxiety, or who are serious about athletic performance, understanding the respiratory-hormone connection can be genuinely life-changing.

How do hormones affect your breathing and lung function?

Progesterone is a direct respiratory stimulant, meaning it increases your drive to breathe and raises the rate and depth of your breath. Estrogen influences airway inflammation and sensitivity. Together, these hormones create a dynamic respiratory environment that shifts throughout your cycle, affecting everything from exercise capacity to sleep-disordered breathing.

The link between sex hormones and breathing is well established in the research literature. Progesterone, which rises during the luteal phase after ovulation, acts on the brainstem to stimulate the respiratory centre. This increases what is called minute ventilation, the total volume of air you move in and out per minute. Studies have shown that progesterone raises ventilatory drive and lowers the threshold at which your body responds to rising carbon dioxide, meaning you breathe more and faster than you would otherwise need to at rest.

Estrogen, on the other hand, has a more complex relationship with the airways. It can upregulate the production of inflammatory mediators and has been shown to influence mast cell activity, which matters a lot for women with asthma or airway hypersensitivity. It also affects the mucous membranes lining the airways, which is why some women notice more nasal congestion or post-nasal drip around ovulation when estrogen peaks.

"Progesterone is one of the most potent endogenous respiratory stimulants we know of. Its rise in the luteal phase creates measurable changes in breathing patterns that can affect sleep, exercise, and how women perceive breathlessness."

Dr. Atul Malhotra, MD, Professor of Medicine, University of California San Diego, Sleep Medicine Division

Does your lung capacity actually change across your cycle?

Yes. Research shows measurable differences in several markers of respiratory function across the cycle. Forced expiratory volume, airway resistance, and peak flow can all vary by phase, with some women experiencing notable dips in the premenstrual window.

A study published in the European Respiratory Journal found that women with asthma were significantly more likely to experience worsened symptoms and reduced peak expiratory flow in the premenstrual and menstrual phases of their cycle, a phenomenon sometimes called perimenstrual asthma. Researchers noted that the sharp drop in estrogen and progesterone before menstruation may trigger airway inflammation and heightened bronchial reactivity in susceptible women. Read the study here.

Even in women without asthma, studies have shown that maximum voluntary ventilation, a measure of how much air you can move in a given time, tends to be higher in the follicular phase and around ovulation, when estrogen is dominant. This may partly explain why many women find cardio-based exercise feels more effortless in the first half of their cycle.

A review published in the Journal of Applied Physiology confirmed that progesterone's stimulatory effect on breathing increases resting ventilation in the luteal phase, which can make moderate-intensity exercise feel harder because you are already breathing at a higher baseline rate.

What happens to breathing during the menstrual phase?

During menstruation, progesterone and estrogen are at their lowest. For many women this means reduced respiratory stimulation, but also a potential increase in airway sensitivity due to prostaglandins released during the breakdown of the uterine lining.

Prostaglandins, the hormone-like compounds responsible for cramping, also act on smooth muscle in the airways. Some women with asthma report their worst breathing episodes during the first days of their period, not the days before. This is thought to be driven by prostaglandin-mediated bronchoconstriction, where the airways narrow in response to the same inflammatory compounds causing uterine cramping.

If you notice tightness in the chest, a tendency to cough, or reduced exercise tolerance in the first couple of days of your period, it is worth tracking whether this follows a pattern each cycle. This information is genuinely useful to share with a GP or respiratory specialist.

How does the follicular phase affect breathing and exercise performance?

The follicular phase is generally the most favourable time for respiratory performance. Rising estrogen supports efficient oxygen delivery, airways tend to be less reactive, and many women feel like their breathing and stamina are at their best during this window.

As estrogen climbs through the follicular phase, its influence on nitric oxide production helps blood vessels dilate and supports oxygen delivery to working muscles. Breathing feels more effortless partly because your baseline ventilatory rate has not yet been pushed up by progesterone, and partly because the inflammatory landscape of the airways tends to be calmer.

This is one reason many athletes and coaches who work with cycle syncing prioritise high-intensity and endurance work in the follicular phase through to ovulation. The body is simply operating with fewer respiratory headwinds during this time.

Why does breathing feel harder in the luteal phase?

In the luteal phase, rising progesterone stimulates the respiratory drive, increasing how fast and deeply you breathe at rest. This higher baseline ventilation means that during exercise your respiratory system is already working harder before you even start moving, which can make effort feel greater than it actually is.

This is not a sign that something is wrong. It is a normal hormonal effect. But it can be confusing if you do not know about it, particularly if you track your heart rate or perceived exertion and notice things feel disproportionately hard in the week before your period.

The luteal phase also tends to be when women notice more anxiety-related breathing patterns, including shallow chest breathing, breath-holding, or sighing. Progesterone has anxiogenic (anxiety-promoting) effects in some women, particularly as it drops sharply before menstruation. Anxiety and breathing are tightly connected through the nervous system, so hormonal shifts that increase anxious feelings will often show up in the breath too.

"Breathwork is not a soft wellness add-on. For women navigating premenstrual anxiety or luteal phase fatigue, targeted breathing practices can directly down-regulate the stress response and support respiratory efficiency at a time when the body needs it most."

Dr. Belisa Vranich, PsyD, Clinical Psychologist and Breathing Specialist, Author of Breathing for Warriors

What about sleep-disordered breathing and your cycle?

Progesterone's stimulatory effect on breathing actually offers some protection against sleep apnoea in premenopausal women, which is one reason women have lower rates of obstructive sleep apnoea than men before menopause. When progesterone drops, as in perimenopause or menopause, this protection largely disappears.

This is a clinically important finding. A study in the journal Sleep found that women's risk of obstructive sleep apnoea increases significantly after menopause, when progesterone levels decline permanently. The hormone's role in maintaining upper airway muscle tone and stimulating breathing drive appears to buffer women against the airway collapse that underlies obstructive sleep apnoea during their reproductive years.

Within the cycle, some women notice more disturbed sleep or greater snoring in the luteal phase. While this seems counterintuitive given progesterone's protective role, the combination of increased respiratory drive, altered sleep architecture, and body temperature changes in the luteal phase can all disrupt sleep quality even if apnoea itself is not present.

How can you support your breathing across each phase?

Understanding the hormonal context is the first step. From there, small and targeted practices can make a real difference.

Menstrual phase: gentle and warming

Focus on diaphragmatic breathing and slow exhalation practices during menstruation. If you experience airway sensitivity or cramps, anti-inflammatory support through omega-3 rich foods and warm fluids may help ease prostaglandin-driven tightness. Avoid high-intensity interval training that demands maximum respiratory output on days when your airways may be reactive.

Follicular phase: build and challenge

This is the time to push your respiratory capacity. Cardio intervals, breath-hold training (if you practise freediving or yoga), and high-intensity exercise all benefit from the favourable hormonal environment. Your airways are generally at their calmest and most responsive to training adaptations.

Ovulatory phase: peak performance window

Around ovulation, many women experience their highest pain tolerance, best mood, and strongest exercise capacity. Use this window for your most demanding breathwork, endurance sessions, or performances that require sustained respiratory effort.

Luteal phase: slow down and regulate

With progesterone driving up your resting ventilation, perceived effort during exercise will be higher. This is the time to lean into breathwork practices that activate the parasympathetic nervous system: box breathing, 4-7-8 breathing, or extended exhale techniques. These slow the breath, lower cortisol, and counter the anxiety-driven shallow breathing that many women experience premenstrually.

What about women with asthma?

If you have asthma, cycle-tracking your symptoms is one of the most useful things you can do. Perimenstrual asthma, defined as a worsening of asthma in the days before and during menstruation, affects an estimated 30 to 40 percent of women with asthma. Yet it is frequently underdiagnosed because neither patient nor clinician has connected the timing of symptoms to the hormonal cycle.

Tracking your peak flow alongside your cycle phase over two to three months can reveal a pattern that your doctor can act on. Some clinicians prescribe adjusted inhaler dosing in the premenstrual window, or explore hormonal approaches to stabilise the estrogen and progesterone fluctuations that trigger flares. This is a conversation worth having.