Help! Irregular Periods And Unusual Menstrual Bleeding Explained

Especially for teens, irregular periods can be a normal thing that comes with puberty. However, there are lots of other reasons why you could be experiencing irregular bleeding, which we will cover in this post. 

Getting your period is already irritating enough, so getting your period at times you don’t expect it – or not at all – is a serious ugh. Don’t worry — it’s probably nothing serious.

Especially for teens, irregular periods can be a normal thing that comes with puberty. Your body is still getting to grips with its menstrual cycle, and you may find that your periods will settle down with time.

Having said that, there are some why reasons you might be getting irregular periods — including your biology, stress levels, and the type of birth control you are taking.

Here are all the reasons why you could be experiencing irregular periods or have unexpected mid-month flow.

Two main causes of irregular periods in women & teens

There are two types of irregular bleeding, the first being breakthrough bleeding. This happens when you experience period blood and menstruation when you don’t expect it, for instance in between your normal cycles.

On the other end of the scale, is when you stop having periods all together, or they become less frequent and don’t conform to a “usual” monthly cycle. You may find you get periods every three months, or even less frequently.

Causes of breakthrough bleeding

Birth control

If you’ve just started birth control or have switched to a different type of contraceptive pill, your hormones will be out of sorts. Birth control is designed to change your usual hormonal cycle, and this can cause bleeding between cycles. But don’t worry – this should even out on its own after a few months. If it doesn’t, talk to your doctor about trying a different brand of birth control or another alternative.


Endometriosis is a painful condition causing the lining of your uterus to grow outside the uterus. Yes, it’s as unpleasant as it sounds. It’s been estimated about 6-10% of women have endometriosis, with it being most common in women ages 30-40. On top of the pain, this condition can cause spotting between your regular cycles. Treatment for endometriosis depends on the severity of your condition. In mild cases, it can be treated with painkillers. If it worsens, your doctor may put you on birth control to treat the symptoms and in some cases, surgery can be performed to remove the tissue growing outside the uterus.

Polycystic ovary syndrome (PCOS)

PCOS is a condition caused by the imbalance of androgens (male sex hormones) which leads to the growth of small cysts inside the ovaries. As a result, women with PCOS don’t ovulate regularly, causing bleeding at unexpected times. PCOS can be treated by improvements to your eating habits or exercise regimen, or by taking birth control to regulate your cycle.


The thyroid is a butterfly shaped gland located in your neck. Your thyroid gland is responsible for regulating your metabolism and releases important hormones into your body. If your thyroid gland is overactive or under-active, irregular bleeding can occur. Some additional symptoms can include excessive sweating, sensitivity to cold and a rapid heartbeat. If you suspect you have an issue with your thyroid gland, your doctor can test its functionality by performing a blood test and will prescribe medication accordingly, depending on the results.

Your cervix

The blood shed from your uterus during your menstrual cycle is released in the same place blood from your cervix would flow – your vagina. The difference is your uterus shedding is normal and expected while blood from your cervix is an indicator of an underlying issue. There can be various causes for cervical bleeding, with the scariest being cervical cancer. (Other causes include STIs like chlamydia).  

Before you freak out, cervical cancer is extremely rare and both cervical cancer and chlamydia are treatable once diagnosed.

The important lesson to take from this is you should be making regular visits to a gynaecologistas these are the professionals who will catch this sort of issue. If you’ve never been to a gynaecologist, speak to your family doctor and they will be able to refer you to someone.

Disruption to your monthly cycle: missing periods

In addition to breakthrough bleeding, no bleeding is considered a form of irregular bleeding. This applies to adults who have never gotten their period or people whose monthly cycles have abruptly stopped happening. Missing a period can be scary, but it doesn’t necessarily mean that you are pregnant. Other than pregnancy, there are a variety of reasons this could be happening, including:

Too much exercise

Being active is great and has so many positive benefits for your mind and body. However, if you’re pushing yourself too hard it can have a negative effect on your body and overall health. If you’re going too hard at the gym and pushing your body further than it wants to go, your body won’t be able to produce enough estrogen to complete its menstrual cycle. If this happens at least three months in a row it becomes categorized as a condition known as amenorrhea, which is prominent among gymnasts, dancers and other professional athletes.

Your weight

A healthy body weight is directly related to a regularly occurring cycle. If you are slightly underweight or overweight you can affect the gland in your brain responsible for regulating some of your body’s usual processes, like producing estrogen. Additionally, a major drop in weight or a low-caloric diet can prevent the body from producing estrogen and in turn deter Aunt Flo from coming to town. Here are some of the best foods you can eat during your period.


Your mental health is just as important as your physical health! Any form of stress can cause a condition known as hypothalamic amenorrhea, which happens when the area of your brain where hormones for your period are regulated stops functioning properly. Whether it’s a breakup, a bad mood or a pile up of work at school, the stress we carry can affect our period.


As crazy as it sounds, when you’re sick your body goes into fight or flight mode, meaning every inch of your body becomes focused on getting rid of the unwanted infection. Sometimes your body can be so focused on its intruder it sacrifices other bodily functions, often your period. So, if you have a cold or the flu don’t be alarmed if your period decides to skip out for that month.

Birth control

There’s tons of different kinds of birth control out there, including pills that give you a period once every three months or once a year. With birth control, it’s also possible to skip your period if you continue to take the hormone pills. As mentioned, many doctors put patients with endometriosis on birth control to prevent their period from coming because having your period can make your symptoms worse if you suffer from endometriosis. If you’re considering using birth control to skip your period, ensure you speak with a physician. 

Irregular period FAQs

Are irregular periods dangerous? Are irregular periods more common in teens?

Not necessarily! They definitely are more common amongst teenagers, so don’t freak out. It’s just good to rule everything out and ensure that nothing else is going on, especially if you have other symptoms like bloating, swelling or pain.

Is missing periods normal?

Sometimes, yes. There are a variety of reasons why your body could skip out on periods, so it’s important to have a look at your overall health and speak to a professional if you are concerned.

Why would I miss a period?

It could be stress, hormonal changes, or the birth control you use. In order to find a solution to irregular periods, you may need to talk to a professional who can get to the bottom of things with you.

How long do irregular periods last?

That depends on why you’re getting them. If it’s just stress making you miss a period, you could just miss out on them for that one month, whereas breakthrough bleeding and spotting can go on for longer.

Are irregular periods something that come with birth control?

Not necessarily, but they are linked. The use of birth control can make your body react in this way, so if you’re experiencing irregular bleeding and you’ve just started the pill or have recently switched to a new one, you might have to change your contraception.

Are there any home remedies I should try?

You can make sure you are taking care of yourself, like eating well and getting the right amount of exercise.

Are irregular periods something to do with ovulation and fertility?

Not always. As well as genetics, lifestyle and diet have a role to play in your menstrual cycle.

Your body is your temple and it’s important to take care of it, so it functions at its best. If you are experiencing irregular periods, don’t panic. As you can see, there are many reasons this could be happening and it’s important to know that in many cases an irregular period is normal. If you’re concerned about your symptoms or you believe your symptoms correlate with some of the conditions talked about in this post, get in contact with your doctor or start seeing a gynaecologist regularly.  

And if you experience frequent breakthrough bleeding, our period panties like this bikini are a great option for those moments when you need a bit of extra coverage.

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