Periodos
Missed or late periods
Revisado: 4 de octubre de 2026
Solo en inglés por ahoraA late or missed period is common and often not serious. Pregnancy is one reason, but stress, weight changes, exercise, contraception and some health conditions can also play a part.
Pregnancy is one possible reason
If you have had sex, pregnancy is the first thing to think about, because a missed period is often an early sign of pregnancy. Periods stop during pregnancy. If there is any chance you could be pregnant, take a pregnancy test. Breastfeeding can also keep periods away. For some people they do not return until breastfeeding ends.
Other common reasons
Late or missed periods have many causes, and most of the time it is nothing to worry about. Stress is one of them. Severe stress that lasts a long time can upset the signals from your brain that control your cycle. Sudden weight loss, large changes in weight and doing a lot of exercise can also delay or stop periods. Some hormonal contraception, such as the pill, the contraceptive injection and the hormonal IUD (coil), can mean you miss periods.
Health conditions to know about
Sometimes missed periods point to a health condition. These include polycystic ovary syndrome (PCOS, now also called PMOS), an overactive or underactive thyroid, diabetes and heart disease. Other hormone problems can also stop periods. Eating disorders, especially anorexia, can stop periods too. Periods can also become less regular and skip months in the years before menopause. Menopause usually happens between the mid-40s and mid-50s.
When to see a doctor or nurse
Even when it is nothing serious, it is worth getting checked. See a doctor or nurse if you have missed 3 periods in a row, or have had no period for 3 months, and you are not pregnant or breastfeeding. Also go if your periods have not started by age 15, or if they have become irregular. The same applies if a missed period comes with weight gain or loss, tiredness, extra hair on your face, or dry or oily skin. Logging your periods in Ciclo can help you see exactly how long it has been.
When to get urgent help
If you might be pregnant, even without a positive test, contact a doctor or nurse the same day if you have pain low down on one side of your tummy or any bleeding. Get emergency help for sudden, severe tummy pain, pain in the tip of your shoulder, heavy bleeding, or feeling very dizzy or faint. These can be signs of a pregnancy growing outside the womb (ectopic pregnancy).
This is general information, not a diagnosis. If you have missed periods or could be pregnant, talk to a doctor or nurse.