Skip to main content

Why Your Period is Late: Identifying Causes of Irregular Periods

Why Your Period is Late: Identifying Causes of Irregular Periods

Menstruation can be uncomfortable for many women or assigned females at birth (AFAB) people. Cramps, mood swings, and breakouts frequently occur during the monthly bleeding, making it unbearable to do daily activities.

It gets worse if the menstruation cycle becomes unusual. One may experience more intense cramps, mood swings, and breakouts. Let's not forget the confusion, wondering why they have irregular periods.

If you experience this issue, you should learn the causes of irregular periods. Simply hoping the condition goes away on its own or overthinking the worst scenario will only do more harm than good.

Let's identify the causes behind your periods irregularity, as explained in this article!

What are irregular periods?

Women or assigned females at birth (AFAB) people will experience menstruation after puberty up until menopause. The average cycle is 28 days, whilst a 23 to 35-day cycle is also common.

Menstrual cycles shorter or longer than 23 to 35 days are considered irregular periods. At some point in their lives, women or AFAB people will experience irregular periods, particularly during early puberty and menopause transition.

It only gets concerning if the irregular periods occur frequently. For instance, a 22-year-old woman who doesn't have menstruation for 3 months for the second time in a year. In this case, they may have health problems that require medical care.

What are the symptoms of irregular periods?

Irregular periods are generally self-diagnosable, which means you can determine it on your own by learning the signs. As noted by NHS, the following are the symptoms of irregular periods:

  • Bleeding in between periods – known as spotting
  • Bleeding after penetrative sex
  • The number of days between your periods keeps changing
  • Earlier or delayed periods
  • Changes in the amount of menstrual blood from one period to the next

The symptoms may or may not indicate health problems. That depends on whether or not you're pregnant, planning to conceive, and your age. It’s best to seek medical advice if you’re unsure, rather than trying to self-diagnose.

In addition, if you experience any of the signs, you may benefit from tracking your period cycle. You can use a menstrual cycle tracking app or write it down on your calendar to understand your cycle, notice any changes, and identify underlying health conditions.

What are the causes of irregular periods?

Irregular periods can be a frustrating and uncomfortable experience for anyone with an ovary. While some degree of its occurrences is expected, several causes potentially lead to more significant changes in menstrual patterns.

The following are some of the causes of irregular periods, which you need to be aware of in case you're experiencing one or more of these:

Hormonal changes

One of the most common causes of irregular periods is hormonal changes. Estrogen and progesterone levels fluctuate throughout a woman's menstrual cycle, which may impact the timing and duration of their periods.

This is particularly common during early puberty and menopause transitions when the body undergoes significant hormonal changes. Otherwise, it's different when an adult woman who is still far from hitting menopause experiences it.

Periodical hormonal changes in an adult woman can indicate underlying physiological conditions or poor diet habits. When they experience it, the body is trying to tell them something is wrong on the inside, which manifests as menstrual irregularities.


Stress is another cause of irregular periods in a variety of ways. First, when you experience stress, your body releases the hormone cortisol, which can disrupt the hormones responsible for regulating your menstrual cycle.

As a result, the timing and duration of your periods may change. Other symptoms, such as cramping, bloating, and mood changes, may also occur when you experience irregular periods due to stress.

Being in a constant state of 'fight or flight' mode that stress entails harms your body. This can lead to more severe and persistent menstrual irregularities.

For that reason, you need to manage your stress levels. You may do so by practising relaxation techniques, such as yoga, regular exercise, getting enough sleep, and seeking mental health professional support if needed. 

Weight gain

Weight gain can impact menstrual irregularities in a variety of ways. First, weight gain is often followed by an increase in body fat, which leads to an increase in estrogen levels. When this happens, the uterine lining thickens and leads to irregular periods.

This is particularly true if the weight gain is rapid or significant. This is due to the weight gain-induced hormonal imbalance becoming more severe, which increases the possibility of irregular periods.

For this reason, if you experience menstrual irregularities after gaining significant weight, you may want to manage your weight. Exercising and maintaining a healthy diet are two methods you can try to gradually lose weight.

Birth control

Hormonal birth control, such as pills, patches, and hormonal IUDs, works by delivering synthetic hormones meant to prevent pregnancy. The process leads to altered natural hormonal balances, which cause irregular periods.

The menstrual irregularity from birth control is because the hormones in the birth control prevent the uterine lining from thickening. Hence you may experience lighter bleeding or no bleeding at all.

Aside from that, stopping birth control after long-term use may also cause irregular periods. It's because the body is trying to adjust to the new hormonal balance, and that's why menstrual irregularity often occurs at this moment.

It's important to note that irregular periods due to birth control are harmless and don't require medical treatment. However, talking with your doctor can help if you have other symptoms occurring, such as pelvic pain or heavy bleeding.


It's common for many women to experience implantation bleeding that occurs one to two weeks after conception. Implantation bleeding is usually light and looks like spotting. That's why some women confuse it with irregular periods.

This condition is harmless and can be a good sign if you've been planning to conceive. But you may need to check whether the light bleeding is caused by pregnancy by getting yourself a pregnancy test.

Menopause transition

Irregular periods are common during the menopause transition, known as perimenopause. It's because the body undergoes significant hormonal changes as a woman approaches their menopause stage.

The body usually starts to produce less estrogen during perimenopause, which leads to irregular menstruation. The symptoms may include shorter or longer cycles, as well as unpredictable cycles.

You shouldn't worry too much, as irregular periods during perimenopause are expected. However, if you experience any unusual symptoms like heavy bleeding or bleeding between periods, seeking medical help can help in identifying the underlying health conditions.

Medical conditions

Several medical conditions can lead to irregular periods, such as polycystic ovary syndrome (PCOS), eating disorders, endometriosis, and thyroid disease. 

If you suspect that you may have any of the following issues, consulting a medical expert is recommended:


PCOS is a hormonal disorder that can cause periods irregularity. Other symptoms, such as acne, weight gain, and excessive hair growth, are also common for people with PCOS.

The root of PCOS is an excess of androgens or male hormones in the body. Having high androgen levels can interfere with ovulation and menstrual cycles.

Eating disorders

Eating disorders such as anorexia and bulimia disrupt the nutrition intake. This makes someone suffering from an eating disorder lack the necessary vitamin, which leads to hormonal imbalances.

When hormonal balances in the body are disrupted, it can interfere with ovulation and menstrual cycles. Hence, it's common for someone with an eating disorder to have skipped periods for a few months.


Endometriosis is a condition in which uterus tissue grows outside of the uterus. Someone struggling with endometriosis often experiences pelvic pain, heavy bleeding, and irregular periods.

Should I be worried about irregular periods?

Having irregular periods is generally something you shouldn't worry about too much. Almost every woman experiences menstrual irregularity at least once in their life.

If you experience this condition, try to look at the severity of your symptoms. If they're still amendable, then you can resolve them by managing stress, maintaining a healthy weight, and using birth control as instructed.

However, if your menstrual irregularity persists, you may want to get yourself checked. For instance, frequent spotting between periods may indicate an issue within your reproductive system.

Check also for other possible medical conditions, such as PCOS, eating disorders, or endometriosis, particularly if you have a family history of these diseases. Getting medical assistance can help you reduce the frequency of irregular periods.

What is the best way to deal with irregular periods?

Irregular periods are uncomfortable to experience. But that doesn't mean you can't deal with it. There are several ways that you can reduce the discomfort, stress, and painful sensations, as explained below:

Store necessary medications

Storing medications at your home can be helpful in case you're experiencing any painful sensations due to irregular periods. Over-the-counter painkillers like paracetamol, ibuprofen, or aspirin can be your choice to make menstrual-induced pain more bearable.

Buy some snacks

Irregular periods may induce body aches, mood swings, and sleep disturbance. Rather than dwelling in your misery, you may want to cheer yourself up by buying some snacks.

Chocolate, candies, and ice creams are some of the sweet snacks that can help you lift your mood. When you eat sweets, your body releases happy hormones, which are good for regulating your mood.

However, remember that you need to eat sweets moderately. Eating too many sweets can lead to weight gain, which further increases your risk of irregular periods.

Take some rest

There's no better way to deal with the uncomfortable effects of irregular periods than taking some rest. Ensure that you have enough sleep throughout the night and lay your body down anytime you feel like it's too painful to stand up.

Forcing yourself to participate in daily activities can make the aches become worse. So, be gentle with yourself.

Prepare yourself for unexpected menstruation

Since you're experiencing irregular periods, your menstrual cycle may come unexpectedly. It's also common to have light bleeding or spotting due to menstrual irregularities.

Many women prepare themselves with sanitary pads. However, pads are sometimes irritating, and they're uncomfortable to wear. This can further add to your distress.

Opting for cute and comfortable period underwear can be your choice. Period underwear comes in a variety of absorbency levels, which you can choose depending on your needs.

Benefits of using period underwear during irregular periods

Aside from looking chic, period underwear brings several more benefits. Below are some of the advantages that it entails:


Period underwear looks and feels like any regular underwear. This allows you to remain comfortable during your monthly bleeding. Time to say goodbye to bulgy pads that are uncomfortable to use.

Eco friendly

An estimated 5 - 15 thousand pads and tampons are used by each menstruating individual in their lifetime. The plastic presents in pads and tampons has a significant impact on the environment. 

On the other hand, period underwear is washable and reusable, making it an eco-friendlier alternative to accompany you during that time of the month.


Period underwear blends well with your body, just like regular underwear does. This way, you can wear any tight-fitting outfits without worrying about any bulges showing from the outside.

Final Thoughts

There you have it, the causes of irregular periods.

We hope that after reading this article, you understand that menstrual irregularity is common. This is especially true for teenage girls experiencing their first period and women approaching menopause.

Despite being common, this condition can be distressing. For that reason, you need to ensure that you know how to comfort yourself during this time. That includes preparing medicines, snacks, and period underwear that protects you during the bloody days.

Mooncheeks, Period Underwear Designed For Bloody Good Times

Mooncheeks offers comfortable and breathable period underwear that keeps girls and women protected during their bloody days. From extra light, light, and medium to heavy absorbency, we have you covered.

Time to say goodbye to boring, uncomfortable sanitary pads and hello to Bloody Good Times with chic, cute and comfortable period underwear from Mooncheeks.

Shop your favourite piece today!

Your Cart

Your cart is currently empty.
Click here to continue shopping.
Thanks for contacting us! We'll get back to you as soon as possible. Thanks for subscribing Thanks! We will notify you when it becomes available! The max number of items have already been added There is only one item left to add to the cart There are only [num_items] items left to add to the cart