Irregular periods: could I be pregnant without knowing?

Why can irregular periods hide a pregnancy?

If your periods have always been unpredictable, a late or missed period may not worry you at all. You are used to them arriving late, or skipping a month altogether. So when a pregnancy does begin, the usual first signal, a missed period, simply does not stand out, and by the time something feels different, more time may have passed than you realise. If this has happened to you, please do not blame yourself. It is common, and it is understandable.

The early signs of pregnancy are also easy to miss, or easy to explain away. Tiredness, mild nausea, tender breasts, a change in appetite or needing to pass urine more often can all be put down to stress or a stomach upset. As a composite example, drawn from many conversations rather than any one person: a woman whose periods have always come every couple of months notices that she is more tired than usual and a little queasy in the mornings. She puts it down to work stress, and only thinks of a pregnancy test much later. Her story is not unusual, and it is exactly why we encourage earlier testing. This guide is by Dr Mayur Pai, MBBS, MS in Obstetrics & Gynaecology.

What causes irregular periods?

One of the most common causes is polycystic ovary syndrome, or PCOS, a hormonal condition in which the ovaries do not release an egg in a regular pattern. Thyroid problems can also disturb the cycle, as can stress, significant weight gain or loss, very intense exercise, breastfeeding, and the months after stopping some hormonal methods of contraception. Sometimes no single cause is found.

Whatever the reason, the result is the same: when cycles are unpredictable, the calendar cannot tell you whether you might be pregnant. It is worth having irregular periods checked in any case, because conditions such as PCOS and thyroid disorders can be managed well once they are known.

Can you get pregnant if you have PCOS?

Yes. This is one of the most common misunderstandings we hear. Many women with PCOS or irregular periods believe they cannot become pregnant easily, and so they do not use contraception. It is true that PCOS can make it harder to conceive when you are trying. But an egg can still be released, sometimes without any warning, and a pregnancy can begin.

So if you do not want to become pregnant, contraception is still important, even with irregular periods. Some methods can also help to regulate the cycle. You can read about the contraception options, and a doctor can help you choose one that suits you.

When should you take a pregnancy test?

With irregular periods, please do not wait for a missed period to tell you. If there is any chance you could be pregnant, for example after unprotected sex or if a condom has broken, and especially if you notice any of the early signs, take a home urine pregnancy test. The first urine of the morning gives the clearest result. If the test is negative but your period still has not come, or the signs continue, repeat the test after a few days or see a doctor.

Keeping a simple record of your periods, on a calendar or a phone app, also helps. It shows you and your doctor what is normal for you, so that a real change is easier to notice.

Why is an early scan so important?

If your test is positive, or you are unsure, come for an ultrasound scan early. For women with irregular cycles, the scan matters even more than usual. The date of the last period is normally used to estimate how far along a pregnancy is, but when cycles are irregular that date can be misleading. The scan measures the pregnancy directly, so its stage is known accurately rather than guessed.

The scan also checks that the pregnancy is inside the womb, and rules out a pregnancy growing outside it, usually in a fallopian tube. That is called an ectopic pregnancy. It is not a normal pregnancy, and treating it is not a termination; it is an emergency that needs different, urgent care. If you have strong pain low in your tummy, especially on one side, heavy bleeding, or you feel faint, go to the nearest hospital straight away.

Why does finding out early keep more options open?

Whatever you decide, earlier is simpler. Finding out early gives you time to think clearly, to talk to the people you trust, and to make your decision without pressure.

If you choose to continue the pregnancy, early care is especially helpful when you have PCOS, because we like to keep a close eye on things such as your blood sugar, blood pressure and thyroid from the start.

If you decide that the pregnancy is not right for you, ending it is lawful care under the Medical Termination of Pregnancy Act, at a government-licensed hospital. Earlier care is simpler and safer, and usually needs less intervention; you can read more about why sooner is simpler. If a procedure is needed, we use 100% single-use disposable instruments, opened fresh for you and never used on anyone else. And every surgical procedure, whether suction or D&C, is done under real-time ultrasound guidance. The doctor watches your womb on the screen throughout, which lowers the risk of complications such as perforation, and the procedure stops at the exact moment the womb is empty, with no unnecessary scraping. That helps protect the lining of your womb for any future pregnancy.

How is your care kept private and in person?

Married or unmarried, you are treated the same, with privacy and respect. Many of the women we see are frightened, and for some it is their first visit to a hospital; our team is used to making you feel welcome rather than judged. Whatever you share with us stays private.

All care is given in person at the hospital in Goa. We do not send any medicine by post or courier, and we do not carry out any abortion by phone. A call, a message or an online consultation can tell you whether treatment is feasible and guide your next step, but the scan, the assessment and any treatment happen when you come in. For a surgical abortion, which is done under anaesthesia, our policy is that you come with a responsible adult who can take you home afterwards; for other types of abortion, you may come on your own.

Getting started

If your periods are irregular and you think you might be pregnant, take a home test now rather than waiting. If it is positive, or you are unsure, call or message us to arrange an early scan. Free patient transport is available from across Goa and nearby areas. This article is for education only and is not personal medical advice; please consult your doctor about your own situation.

Or call +91 75582 52088 · 0832 251 3641

This page is for general education and is not personal medical advice. Treatment depends on your own examination and reports, so please speak to a doctor about your situation. We do not carry out or offer sex determination of any kind.