Bloating before menstruation: hormonal causes and solutions

To understand this phenomenon, you first need to look at the constant dialogue between your hormones and your digestive system. It is not the uterus that swells, but rather your intestines reacting to hormonal changes. Bloating and hormones are therefore closely linked!

Three major mechanisms explain this bloating:

Before your period, progesterone reaches its peak to prepare the body for a potential pregnancy and keep the uterus calm. At the same time, it slows down your intestinal transit. Food and gas linger, ferment, and create that feeling of bloating and a swollen, hard belly. This slowdown can even lead to constipation, increasing your discomfort.

In the luteal phase, if estrogen remains high relative to progesterone, your lymphatic system filters less efficiently and your capillaries become more permeable. The result: water accumulates in tissues, making your belly feel heavier and sometimes causing slight weight gain. Fortunately, this excess fluid is usually eliminated within the first days of your period.

Hormones influence receptors in your small intestine and colon: they affect mucus secretion, contractions, and the permeability of the intestinal walls. This combination promotes gas buildup and water retention, increasing bloating. If you already have poor blood circulation, these symptoms can sometimes intensify.

Bloating that lasts 5 to 7 days before your period usually isn’t a concern. That’s how long it takes for your hormones to shift and for your body to rebalance fluid circulation. Sometimes these symptoms can last up to two weeks if your PMS phase is extended, but it is most often physiological.

However, if the bloating persists outside your cycle, is accompanied by intense pain, unusual bleeding, or extreme fatigue, it’s best to consult a healthcare professional to check for underlying issues such as endometriosis or irritable bowel syndrome.

Certain habits can increase bloating. Consider limiting:

• Foods high in fast sugars and FODMAPs (cabbage, onions, lentils), which ferment in the gut.
• Excess salt, which worsens water retention.
• Chronic stress-related bloating, which disrupts the gut flora and intestinal permeability.
• Lack of physical activity, which slows transit even more.
• Not enough sleep, which can contribute to hormonal imbalance and greater sensitivity.
• Alcohol, which irritates the mucosa and produces gas.
• Irritable bowel syndrome (IBS), whose symptoms may be exacerbated by your hormones.

Choose a diet that soothes the lower abdomen, rich in potassium (bananas, tomatoes, asparagus, salmon) to balance fluids. Add ginger, fennel, white rice, cooked zucchini, and probiotics (kefir, fermented yogurt) to support digestion without excessive fermentation.

Drink 1.5 to 2 liters of water per day, plain or infused with lemon, to help your body eliminate excess fluid. Warm herbal teas (chamomile, peppermint) soothe the digestive system.

Infusions of peppermint, chamomile, or fennel relax the intestinal muscles and relieve gas. Turmeric and fresh ginger provide a natural anti-inflammatory effect.

A few minutes of abdominal breathing (inhale through the nose while expanding your belly, exhale through the mouth) calms the nervous system and gently massages your intestines. A short walk after meals can also stimulate transit.

Formulas based on fennel, probiotics, or magnesium can support your gut flora, reduce spasms, and help you debloat quickly during the menstrual phase.