Irregular Periods: Common Causes and When to Worry

Medically reviewed by Dr. Manan Boob — MBBS (KEM), MS ObGyn (Gold Medalist), DNB, Consultant Gynaecologist & Laparoscopic Surgeon, Shubham Hi-Tech Hospital and Test Tube Baby Centre, Amravati.

Very few women track their cycle closely until it starts behaving oddly. Then suddenly the calendar becomes the most-checked app on the phone. A period arrives eleven days late, or twice in one month, or skips altogether — and the worry begins.

Here’s what I tell my patients: an irregular cycle is a message, not a verdict. Your periods are one of the most sensitive barometers your body has. When something else is off — thyroid, weight, sleep, stress, hormones — the cycle is often the first thing to show it. Most of the reasons behind irregular periods are common and treatable. The point is to find out which one is yours instead of guessing for months.

What actually counts as “irregular”

A textbook cycle is 28 days, but almost nobody is a textbook. Anywhere from about 21 to 35 days is normal, and a shift of a few days here and there means nothing at all.

What we pay attention to is the pattern:

• Cycles that keep varying by more than about a week
• Gaps of more than three months with no period
• Bleeding that has become much heavier or much lighter than your normal
• Bleeding between periods, or after intimacy
• A rhythm that used to be predictable and simply isn’t any more

That last one matters more than people realise. A change from your usual is worth more than any number on a chart.

“My period is ten days late but the test is negative — should I panic?”

No. One late period, on its own, is very rarely a sign of anything serious. A stressful few weeks, a bout of illness, travel, a change in sleep or weight — any of these can push a cycle back. Give it a cycle or two. If it keeps happening, that’s when to get it looked at properly.

The usual reasons behind an irregular cycle

PCOS. Easily the commonest cause I see in younger women. Cycles stretch out, ovulation becomes unpredictable, and there may be acne, extra hair growth or weight that’s hard to shift. It is manageable, and often very responsive to the right combination of lifestyle changes and treatment. We’ve written a fuller guide on the signs of PCOS.

Thyroid trouble. An underactive or overactive thyroid can quietly disorder your whole cycle. It is picked up on a simple blood test and is usually straightforward to correct — which is why I test for it early rather than late.

Weight, stress and exercise. Sudden weight loss or gain, crash diets, very intense training, months of poor sleep or sustained anxiety all disturb the brain-ovary conversation that keeps your cycle running. This is real physiology, not “just stress.”

Raised prolactin. A hormone made by the pituitary gland. When it runs high, periods become infrequent or stop, and sometimes there’s a milky discharge from the breasts.

Fibroids, polyps or adenomyosis. These tend to cause heavy, prolonged or in-between bleeding rather than skipped periods, and they show up on a scan.

Perimenopause. In the forties, cycles often shorten, lengthen, then start skipping. This is a normal transition, though heavy or erratic bleeding still deserves a check rather than an assumption.

Contraception and other medicines. Starting or stopping hormonal contraception, or an IUD, reshuffles the cycle for a few months. Certain other medicines do the same.

A quick self-check: is it time to book?

Make an appointment if you can tick any of these:

• Three months or more without a period, and you’re not pregnant
• Cycles consistently shorter than 21 days or longer than 35
• Bleeding heavy enough to soak through protection hourly, or clots larger than a rupee coin
• Bleeding between periods or after intimacy
• Any bleeding after menopause
• Irregular cycles plus difficulty conceiving

“Will irregular periods stop me from getting pregnant?”

Not by themselves — but they often mean ovulation is happening erratically, which makes the timing much harder. The good news is that most causes are treatable, and plenty of women conceive naturally once we sort out what’s behind the irregularity. If you’ve been trying for a year, or six months if you’re over 35, don’t wait it out.

Myth versus fact

Myth: “Skipping periods is fine, it just means less bother.” Fact: Long gaps without a period mean the uterine lining isn’t being shed regularly, which over years can cause problems of its own. Missing periods deserve an explanation.

Myth: “Irregular periods always mean PCOS.” Fact: PCOS is common, but thyroid disorders, prolactin, weight change and stress account for a great many cases. That’s exactly why we test rather than assume.

What to expect at your appointment

Nothing intimidating. We’ll talk through your cycle history — bring your phone calendar or a rough note of the last few months, it genuinely helps. There’s usually a gentle examination and a pelvic ultrasound, plus blood tests chosen to match your symptoms rather than a scattergun panel.

If the scan suggests something inside the uterus, such as a polyp, a hysteroscopy lets us look directly and often treat it in the same sitting, with no cuts at all. You can read more on our Advanced Laparoscopy & Hysteroscopy page.

Most women leave with a clear explanation and a plan that starts simply.

Don’t spend another six months wondering

If your cycle has been unpredictable for a while, the answer is usually simpler than the worry. Our gynaecology team at Shubham Hi-Tech Hospital and Test Tube Baby Centre, Amravati, offers ultrasound, hormone testing and advanced keyhole care in one place, so you get a proper answer rather than another month of waiting.

Call +91-8668954915 to book a consultation, or reach us through our contact page. You can also read our guide to the best gynaecologist in Amravati.

Disclaimer: This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor for guidance specific to your situation.