SPM y síntomas del ciclo

Bloating and digestion changes

Revisado: 4 de octubre de 2026

Solo en inglés por ahora

Many people feel bloated or notice bowel changes before or during a period. This is common, and a few simple steps can help. Here is when to get checked.

Common gut changes around a period

Bloating, a gassy feeling, tummy pain, constipation and diarrhoea are all common before or during a period. They are recognised signs of premenstrual syndrome (PMS). In one survey of 156 healthy women, nearly 3 in 4 had at least one gut symptom before or during their period. About 6 in 10 felt bloated before their period, and about 1 in 4 had diarrhoea. The survey relied on people's memory, so the exact figures are uncertain, but these changes are clearly common.

Why it happens

Before a period, changing hormone levels are thought to make the body hold on to more water, which can leave you feeling puffy or bloated. What you eat may also play a part, and salty food may make you hold more water. During a period, the womb releases chemicals called prostaglandins that make it squeeze. Prostaglandins can also make the muscles of the bowel squeeze and change how it handles fluid, which may explain looser stools for some people.

What can help

Eating less salt may reduce water retention. Cutting down on caffeine, salt and sugar in the 2 weeks before your period may ease many PMS symptoms. Regular aerobic exercise, good sleep and relaxation, such as breathing exercises, yoga or massage, may also help. There is some evidence that magnesium may reduce water retention and that vitamin B6 may ease bloating. Ask a pharmacist before taking supplements, especially if you take other medicines.

Medicines and tracking

If bloating is a big problem, a doctor may prescribe water tablets (diuretics), which can reduce bloating for some people. Taking diuretics together with anti-inflammatory painkillers such as ibuprofen can damage the kidneys, so only use them with a doctor's advice. Hormonal contraception may also help the physical symptoms of PMS. Logging digestion and bloating in Ciclo for a few months can show whether changes follow your cycle or come from something else.

When to get checked

See a doctor or nurse if you feel bloated or have a swollen tummy regularly, or if bloating comes with blood in your poo or losing weight without trying. Also go if you often feel full quickly, lose your appetite, need to pee more often, or have pain in your tummy or pelvis. These have many causes, but rarely they can be a sign of ovarian cancer. Get help the same day if bloating comes with vomiting, a high temperature, a lump in your tummy, or you cannot pee, poo or pass wind. Get emergency help for sudden, severe pain in your tummy or pelvis, or if you are vomiting blood.

This is general information, not a diagnosis. If bloating or bowel changes happen often or do not follow your cycle, see a doctor or nurse.