Irregular or absent periods are common in PMOS/PCOS. Learn why long gaps between periods matter, what to track, and when bleeding changes need medical review.
Why periods can become irregular
PMOS/PCOS often affects ovulation. When ovulation happens infrequently or unpredictably, periods can become widely spaced, absent or irregular. Some people have frequent or heavy bleeding instead. A cycle tracker can help describe the pattern, but it cannot tell you the cause by itself.
Long gaps between periods deserve attention
The international PMOS/PCOS guideline notes that premenopausal women with the condition have a higher risk of endometrial hyperplasia and endometrial cancer, although the overall chance of developing endometrial cancer remains low and routine cancer screening is not recommended for everyone. Long-standing untreated amenorrhoea is one factor that can increase risk.
The practical message is not to panic about every late period. It is to avoid going for long stretches without clinical review when periods are repeatedly absent or very infrequent.
What to record
- First day of each period
- Number of days of bleeding
- Whether bleeding is light, moderate or heavy
- Spotting between periods
- Pain or other symptoms
- Pregnancy tests when relevant
- Hormonal contraception or medicines that affect bleeding
Bring several months of data if you can. That makes it easier for your clinician to distinguish a chronic PMOS pattern from a new change that may need investigation.
When to seek medical advice
Contact your clinician if you are going long periods without bleeding, if periods suddenly become much heavier or more frequent, if you bleed after sex, or if you develop new pelvic pain. If you have gone 12 months without a period because of menopause and then bleed again, that is postmenopausal bleeding and should be medically assessed.
Seek urgent care for extremely heavy bleeding associated with dizziness, fainting, shortness of breath, chest pain or severe weakness.
Treatment is individualized
Depending on your goals and health history, clinicians may use hormonal contraception, cyclic progestogens, metformin or other approaches to manage cycles and reduce risk. Fertility goals, contraception needs, metabolic health and personal preferences all affect the plan. Do not start or stop hormone treatment based on an online article.
Why a tracker is useful even if cycles are unpredictable
Irregular cycles can feel impossible to describe. A simple record turns “my periods are all over the place” into information a clinician can use: how long the gaps are, whether bleeding is getting heavier and how symptoms change over time.
Track the pattern, not just the period date
The PCOS Wellness Planner includes six monthly cycle and symptom trackers plus appointments, test results, medicines and weekly planning pages.
