What does an irregular menstrual cycle mean?

If the first day of your period falls on a different date every month and there's no way you can predict when the next one will start, you most likely have an irregular menstrual cycle. Don't worry: every girl and woman is different, and an irregular cycle isn't automatically a warning sign.

Think you might have an irregular cycle too? Then it's perfectly normal for plenty of questions to be going through your mind. Why does a cycle become irregular? How do ovulation and pregnancy work with an irregular cycle? When does it become a cause for concern, and when should you see a doctor? The right questions in the right place! Let's talk it through in detail – we'll share everything we know about these cycle disorders.

What does an irregular menstrual cycle mean?

An irregular menstrual cycle is when the length of your cycle (the time between the days your period starts – theoretically around 28 days) changes every time. In other words: your period either arrives early or it's late.

For some girls the cycle lasts 27 days, for others 30 days – as long as this length doesn't change, or stays similar from month to month, the cycle is regular. However, if this interval is shorter in some months and longer in others, we're talking about an irregular menstrual cycle.

Causes – why does the menstrual cycle become irregular?

There are an enormous number of possible causes for cycle disorders. In many cases it's simply normal and natural for your body – and therefore no cause for alarm.

In other cases, there are a few possible reasons why you don't have a regular, predictable cycle, including:

• Puberty – an irregular cycle is completely normal, especially in the first 1–2 years after your first period;
• Pregnancy – changes to your cycle can occur at the end of pregnancy, after birth, or indeed at the very beginning of pregnancy: a pregnancy test will give you an answer straight away;
• The menopause – at the onset of the menopause, often between the ages of 45 and 55, your cycle can become irregular;
• A sudden change – significant weight loss or gain, stress or excessive exercise can throw your cycle off balance;
• Endometriosis – can be a cause of an irregular cycle and spotting between periods;
• Polycystic ovary syndrome (PCOS) – girls and women with PCOS don't ovulate, or ovulate less frequently, which leads to an irregular cycle or even no periods at all.

 Cycle disorders in adolescents

An irregular cycle in adolescents is normal. All the more so when it isn't accompanied by other health problems or pain – in which case there's no reason to worry if parents notice cycle irregularities at, say, 13 years of age.

These days, most girls have their first period between the ages of 10 and 15. Of course, every body is different: for some girls it may start earlier, for others considerably later. During adolescence, periods can come and go for all sorts of reasons. Ongoing growth and physical development can also cause an irregular cycle during puberty.

That's why it can be perfectly normal for a girl of 14 to notice cycle irregularities. It can even take up to 2 years for the cycle to settle into a pattern – and during this time, changes in weight, stress or general health will continue to influence these fluctuations.

 Irregular cycle after giving birth

During pregnancy there's no ovulation, and consequently you don't have periods either. When your period does return – often 4 to 6 weeks after the birth – it happens in your body's own natural rhythm.

After pregnancy, your periods can be very varied and irregular. The length of your cycle may change, as may the number of days you bleed. It's also not unusual to skip a period one month, or for it to be delayed by several months.

The important thing is to stay calm – an irregular cycle after giving birth is absolutely normal, particularly in the first few months and especially if you're breastfeeding. The hormones that support breastfeeding can delay ovulation or make it irregular, causing an irregular cycle while you're nursing.

Cycle disorders after first having sex

If you've started having sex, it's not unusual to notice a change in your cycle. It happens to lots of girls, and it's normal. Sexual activity can trigger various changes in your body.

Although it is possible, a late period doesn't always indicate pregnancy. But if the question is playing on your mind, a pregnancy test will give you the quickest answer.

Note: it is NOT sexual activity itself that causes these disruptions! It's arousal, which can trigger numerous hormonal fluctuations that contribute to a temporary delay in your period.

Oxytocin, too – the so-called love hormone released during orgasm – can reduce stress and affect your cycle.

Cycle disorders during perimenopause

If you notice your cycle becoming irregular at around the age of 45 to 55, this is one of the clearest signs of perimenopause. During this transitional phase, various types of cycle disorder can occur, including changes in how heavy your bleeding is and bleeding that appears irregularly.

Periods may gradually become less frequent until they stop altogether. If you haven't had a period for 12 months, you're considered to have reached the menopause.

 Cycle disorders – signs & symptoms

The signs and symptoms of cycle disorders are easy to spot and you'll notice them without difficulty. They're precisely the changes you can observe from one period to the next:

• Your periods seem to be moving further apart, meaning one period starts more than 35 days after the end of the previous one;
• Your periods seem to be moving closer together, meaning one period starts less than 25 days after the end of the previous one;
• The number of days a period lasts is different every time;
• The number of days between one period and the next is always different;
• The heaviness of your bleeding changes from one period to the next.

Types of cycle disorder

Every girl experiences the symptoms described above in her own unique way. That's because an irregular cycle can take various forms.

It isn't only changes in frequency that count as a cycle disorder, but also changes in duration, heaviness of bleeding and symptoms. So there are several types of cycle disorder – depending on the number of periods per month or year, the amount of blood lost and the interval between periods.

Polymenorrhoea – an irregular cycle with periods twice a month

Polymenorrhoea, or overly frequent menstruation, refers to bleeding that occurs more often than normal. An irregular cycle with two periods a month – more precisely, with an interval of less than 21 to 24 days – is classed as polymenorrhoea.

If, for example, you have an irregular cycle of 15 days, that's called polymenorrhoea. Girls and women with this form of disorder have a normal flow. It's only the frequency that's atypical, and it can often lead to anaemia, water retention or bloating.

Oligomenorrhoea – periods occurring more than 35 days apart

At the other end of the spectrum is oligomenorrhoea. This form of cycle disorder consists of irregular periods where more than 35 days pass between your last period and the start of the next.

Although oligomenorrhoea isn't a worrying condition in itself, it can be underpinned by other problems that need treating – eating disorders, for example.

Amenorrhoea – absence of periods for several months

Unlike oligomenorrhoea, where periods occur less frequently, amenorrhoea is defined as the absence of periods for one or more months and means a complete lack of menstruation over several months. There are two forms of amenorrhoea:

• Primary amenorrhoea: the absence of periods in girls who have already reached the age of 15; this is often influenced by hormone levels or anatomical factors.
• Secondary amenorrhoea: the absence of 3 or more consecutive periods, despite having had periods previously; pregnancy is the most common cause, but there can be other reasons too, such as a hormonal imbalance.

When should you see a doctor?

An irregular menstrual cycle usually isn't cause for alarm. Especially if you're still going through puberty, or you know you've always had irregular periods.

That is, of course, as long as you keep up your regular visits to the gynaecologist. These are so important – above all for your own peace of mind (who better to answer your questions than your doctor?), but also to catch and treat other problems early.

Even so, there are certain cases where cycle disorders can point to more serious problems. So don't hesitate to book an appointment with your gynaecologist if:

• you've had periods before, but haven't had one in the last 3 to 6 months
• you experience bleeding between periods, after sex or during the menopause
• your period lasts longer than 7 days
• you notice a big difference (more than 20 days) between your shortest and longest cycle
• your period starts less than 21 days or more than 35 days after the previous one
• you're under 45, have always had regular periods and they suddenly become irregular
• you want to get pregnant but have an irregular cycle

Ovulation & pregnancy with an irregular cycle

Whether you want to get pregnant or avoid an unplanned pregnancy, knowing the phases of your cycle and working out your most fertile days can help. Of course, this is in no way a contraceptive method, but it can be useful to calculate your fertile window – we've talked about this before in our blog post on what the fertile window means.

Bear in mind, however, that calculating pregnancy and ovulation with an irregular cycle is difficult:

• The calendar method is ruled out from the start.
• The accuracy of any online ovulation calculator for irregular cycles is low.
• It's impossible for an online pregnancy calculator to give a 100% accurate result with an irregular cycle when the cycle length isn't constant.
• The greatest accuracy comes from an ultrasound scan, which shows exactly which week of pregnancy you're in.

And despite all that – what can you do? You want to get pregnant. You don't know how many days your period lasts. You don't know when the next first day of your period will be. Here are a few methods for roughly working out the fertile window in women with an irregular cycle:

1. Track and record your cycle. Even if the calendar method doesn't work, following the pattern on a calendar might reveal a few clues.
2. Estimate your ovulation: every woman ovulates roughly 14 days before her next period, regardless of cycle length. Count back 14 days from the first day of your current period to estimate the day you ovulated.
3. Observing cervical mucus remains a reliable method. Clear, stretchy discharge indicates ovulation and fertility.
4. Use an ovulation test. If you detect a surge in luteinising hormone (LH), it means ovulation is likely to begin within the next 24 hours.

Complications of cycle disorders

In principle, cycle disorders aren't dangerous. Even so, disorders that persist over the long term or radical changes can increase the risk of other conditions and cause complications such as heavy bleeding, severe pain and cramps, or bleeding between periods.

With oligomenorrhoea and amenorrhoea, infertility can be one of the most serious complications, since ovulation happens rarely or not at all. With polymenorrhoea, the high blood loss can lead to anaemia and iron deficiency. These can in turn cause dizziness, nausea and vomiting, headaches, confusion, memory problems and so on.

Treating cycle disorders

If the disruption is only mild, you could try a tea for irregular cycles. If you're still going through puberty, your gynaecologist might also recommend natural remedies to help regulate your cycle, such as raspberry shoot extract.

Don't forget that every girl's and every woman's body is different – your treatment will be individual and unique. The solution your doctor recommends for an irregular cycle will depend on the underlying cause and your medical history. It might involve medication, hormones or even surgery.
 

Hormonal treatment 

If perimenopause is causing your cycle disorders, your doctor may recommend hormone therapy with oestrogen and progesterone. This can also help with other menopausal symptoms: hot flushes and vaginal dryness.

It can be used as a tablet as well as a cream, spray, capsule or vaginal ring. 
 

Medical treatment

If endometriosis, PCOS, fibroids or other conditions are causing your irregular or heavy bleeding, you may be prescribed medication for hormonal disorders.

The pill can help both to treat the hormonal cause and to regulate your cycle. Heavy bleeding is also treated with medication (tranexamic acid), as is an infection causing irregular bleeding (antibiotics) or unbearable cramps (ibuprofen).

Surgical treatment 

Depending on the condition, your age and whether or not you'd like to become pregnant in the future, there are also surgical treatment options for an irregular cycle.

These may include removing uterine fibroids that are causing the disruption, endometrial ablation to reduce the heaviness of bleeding, or uterine artery embolisation, which stops blood reaching the uterus and thereby eases the symptoms caused by fibroids.

How can you prepare for irregular cycles? 

Whatever kind of disruption you're dealing with – too many periods or too few – irregular cycles can be frustrating and stressful. Especially when you're not prepared and the first day of your period catches you out just when you least expect it. Fortunately, there are a few ways to get prepared, even if your irregular periods are full of surprises:

• Is the gap between your periods more than 35 days? Make sure you always have a period kit in your handbag. If you never know when your next period will start, you don't know when you'll need a tampon or a pad to hand, do you? Always having your little rescue kit at the ready can save you from plenty of awkward moments!
• Polymenorrhoea? Use panty liners so you're covered at the very first sign. If your period comes twice a month, you need to be ready at any time. Sometimes light discharge in your underwear goes unnoticed, but a panty liner shows you straight away when bleeding starts – helping you avoid stains and unpleasant surprises.
• Heavy flow? Uncomfortable as they are, fluctuations in flow CAN be managed! You don't have to live day in, day out worrying that your protection isn't up to the job. Enroush pads and tampons come in a range of absorbencies so they fit your body perfectly!

Choose your period kit for an irregular cycle carefully – it can be the key to always being prepared.

Enroush's mission is to make period products made from purely natural materials accessible to you – with 100% organic cotton and no hidden ingredients. You deserve to know and decide what comes into contact with your body – and with our products, you already have that control.

Frequently asked questions

We hope we've been able to answer as many of your questions about irregular cycles as possible. Every one of us has questions we struggle to find answers to – in which case, the most expert assessment comes from your gynaecologist.

Even so, below we'll try to answer some of the most common questions about cycle disorders.
 

Can cycle disorders be prevented? 

During puberty, perimenopause, after pregnancy or when other hormonal problems affect your balance, it may be impossible to prevent these disruptions. In all other situations, if you're in good health, the following everyday habits and self-care rituals can help you prevent cycle disorders:

• Live as healthily as you can: a balanced diet and an active lifestyle (without excessive exercise) will help you maintain your hormonal balance.
• Avoid harmful habits: drinking alcohol or smoking can make cycle disorders worse.
• Approach weight loss responsibly: if you want to lose weight, do it gradually with a slight calorie deficit – not radically with drastic diets that cause hormonal imbalances.
• Take the pill exactly as prescribed: if your doctor has prescribed the pill or another contraceptive, follow their advice to the letter.
• Practise relaxation techniques: meditation, breathing exercises, reducing stress and  getting enough sleep can help you maintain your hormonal – and therefore menstrual – balance.
• See your doctor regularly: regular check-ups with your GP and gynaecologist are crucial for preventing and effectively treating any conditions that may arise.
   

Can you work out when your next period is due if you have cycle disorders?

The unpredictability of the next period is precisely one of the defining features of an irregular cycle. It's difficult, in fact almost impossible, to calculate your next period – and that's exactly what's so frustrating. If you note down the start and duration of each period on a calendar, though, following the pattern might reveal a few clues.
 

When should you take a pregnancy test if you have an irregular cycle?

If you have an irregular cycle, you can count 4 weeks from having sex, or 36 days from the first day of your last period. If you're pregnant, your hCG levels should by then be high enough for a test to detect the pregnancy. If you'd like to know more about this topic, you'll find everything about pregnancy tests on the Enroush blog.