Period calendar

Your period is due and every time you go to the loo you pull your pants down in anticipation. But nothing happens. Your period never arrives. With every hour you’re getting a little more worried, thinking “Am I pregnant?!”. This is a scenario that’ll likely happen to most of us at least once. And it can be scary! Especially if a baby isn’t part of your plan at all. But even though pregnancy is a possible reason for your period being late, it’s by far not the only one. So, let’s take a look at what could be causing Aunt Flo to arrive late to the party.

Stressed woman

The good old stress

We all go through periods where our lives are a little more stressful but having much on at work on in school generally doesn’t affect your period. It’s more overwhelming situations like the death of a loved one, a nasty divorce or, well, a global pandemic that can mess up your cycle. Why? Because stress affects the hormonal balance in your body which can quickly lead to irregularities. You might be sitting there, thinking what your brain has to do with all of this. Well, despite popular belief, it’s not actually your uterus that decides when it’s time for a cleanse. It’s your brain that makes the decision. Your uterus is really just the executioner.

Stress doesn’t automatically mean that your period is late or doesn’t show up at all, though. There’s also a possibility that your monthly bleeds get stronger, more frequent, and your cramps can become worse. Either way, if you feel like it’s stress that’s affecting your period, have a chat with your GP about it. They will be able to help you manage your stress effectively.

Woman exercising

Exercise & sports

Have you recently upped your exercise regime to the extreme? Then that might be the reason why Aunt Flo doesn’t want to visit you this month. We’re not talking about going for a run in the morning and doing some weightlifting in the evening, though. For sports to affect your period, you’ll have to complete hours and hours of seriously strenuous exercise each and every day. And, frankly, if you’ve not just started training for the Olympics, that much exercise is highly unlikely. Why does extreme exercise affect your period? Easy! Because it causes changes to your body’s hormonal balance which, in turn, will affect your cycle.



There are quite a few medicines out there that can have a knock-on effect on your period. Everything from antidepressants, antipsychotics, thyroid medication, to chemotherapy can mess up your monthly cycle. But the most common one is definitely – you guessed it – hormonal birth control! The pills, implants, plasters, and IUDs of the world can all have different effects. So, using hormonal contraception doesn’t’ automatically mean that your periods will be lighter and less frequent. Some of them can actually cause them to get super heavy and with others you might not bleed at all. Why don’t you bleed, though? Some birth control options out there will keep the lining of your uterus so thin that there’s basically not enough there for you to actually bleed. And even once you stop taking the pill or have your implant removed you won’t be back to your perfect 28-day cycle immediately. It will likely take your body a couple of months or more to find its rhythm again.

BMI Calculator


Weighing too much, weighing too little or experiencing a drastic change in weight can all have an effect on your period. Obesity, for example, is likely going to knock your oestrogen and progesterone levels of balance, causing you to miss one or more periods. If your weight is too low, on the other hand, your body might not have enough resources to actually produce all the necessary hormones to get you bleeding. That is precisely why women with anorexia often don’t have a single period until they start to gain weight again.

If your weight fluctuates quite a lot all of a sudden, this can affect the hormone levels in your body and, in turn, your period. For example, if your weight suddenly drops due to an illness, it’s likely that Aunt Flo won’t be visiting you that month. If that’s the case, make sure to speak to your GP about it as they might be able to prescribe you something to increase your hormone production.

Woman between plants

Menopause and Perimenopause

When you’re nearing the end of your reproductive years, you might notice some changes to your monthly bleeds. They can become lighter or heavier and might happen more or less often. Whatever it may be, you’ll definitely notice a difference. Why does this happen? It’s quite simple, really! As you get older, your oestrogen levels will start to fluctuate which will cause your periods to change. So, if you experience irregular periods all of a sudden, this might be what’s to blame.

How do I know if I’ve actually gone through menopause? There is no set answer but if you haven’t had a single period for at least 12 months then it’s likely that you’ve come out at the other side of it. This also means that you’re no longer able to get pregnant naturally.

Woman breastfeeding


Have you just had a baby and are breastfeeding your little one? Then it’s highly likely that you won’t be getting your period anywhere near as regularly as usual. You might not get it at all! There’s no need to worry about it, though. It’s called lactational amenorrhea and your periods should go back to normal after a few months. If they don’t, however, please speak to your GP about it!

Also don’t be fooled into thinking that you can’t get pregnant just because you’re not getting your period. Breastfeeding is no contraception, and you CAN get pregnant as many women have experienced before. So, if a back-to-back pregnancy isn’t part of your plan, make sure to use contraception!

Woman on leaf

Polycystic Ovary Syndrome (PCOS)

Polycystic Ovary Syndrome, or PCOS for short, is one of the most common hormonal disorders in women before menopause. So, what happens when you have PCOS? Well, let’s start at the beginning. Usually, during your cycle, your ovaries produce about 5 follicles each. These follicles then compete and the dominant one is the one that’ll release the egg when it’s time. When you have PCOS, however, your ovaries will likely produce more follicles which means the whole process takes longer. And as long as your ovaries don’t release an egg, you won’t get your period.

Your follicles and late or missed periods are not the only symptoms associated with PCOS, though. You can also experience weight gain, an increased amount of facial and body hair, as well as male-pattern baldness. If you suspect that you’re suffering from PCOS, for whatever reason that may be, have a chat with your GP. There are treatments available and you don’t have to suffer through it!

Pregnant woman

The obvious one: Pregnancy

Just because there are other possibilities doesn’t mean it’s a good idea to rule out pregnancy completely. Obviously, if there’s simply no way that you could be pregnant, don’t waste another thought on it. However, if you’re sexually active, even if you’re using contraception, make sure to take an at-home pregnancy test if Aunt Flo decides to be a no-show.


Doctor's office

When should you see a doctor?

Missing the odd period is generally no reason to panic and it’s very likely that everything is perfectly fine. However, if you miss two or more periods in a row, it’s definitely important that you speak to someone about it as this should be looked at by a healthcare professional. If you’re experiencing any of the following symptoms in addition to irregular periods, it’s definitely time to get in touch with your GP:

  • New or worsening headaches
  • Changes to your vision
  • Nausea or vomiting
  • Fevers
  • Hair loss
  • Breast secretions or milk production
  • Excess hair growth

1 Reply to "Am I pregnant? Reasons for a late period"

Leave a Reply

Your email address will not be published. Required fields are marked *