Irregular menstrual cycle days explained

Count cycle days from the first day of one period to the first day of the next. Variation can happen when ovulation is delayed or absent, known as Anovulation. Polycystic Ovary Syndrome may cause widely spaced or unpredictable periods. Perimenopause can shift timing as ovarian hormone production changes, and Premature Ovarian Insufficiency can also lead to infrequent periods. Illness, travel, sleep disruption, intense training, weight change, and hormonal contraception may affect the pattern. A late period can also be an early sign of pregnancy.

Use a calendar or app to record bleeding dates, flow, spotting, cramps, medicines, contraception, and relevant symptoms. Bring several cycles of notes to a clinician. They may ask about pregnancy, thyroid symptoms, acne, hair growth, hot flushes, and fertility goals. A pregnancy test is sensible when pregnancy is possible. Testing or treatment is chosen from the history rather than from the calendar alone. The Combined Pill may make bleeding more predictable for some people, but it is not suitable for everyone.

Book an appointment if periods repeatedly disappear, become much closer together, or change with pelvic pain, bleeding after sex, unusual discharge, or symptoms of anaemia such as tiredness and breathlessness. Get urgent help for severe pain, faintness, or heavy bleeding, especially with a possible pregnancy. Prompt assessment is needed for these red flags regardless of how often irregular cycles occur.

Ask what cycle information is most useful, whether pregnancy or hormone tests are needed, and how your contraception, symptoms, and plans for pregnancy change the management options.