Why Is My Period Late? 21 Reasons Other Than Pregnancy To Explain A Late Period

Late Period? No need to sweat it - here's 21 legit reasons why that might be. Illustration by Sophie Cunningham

Why Is My Period Late? 21 Reasons Other Than Pregnancy To Explain A Late Period

by Kat de Naoum |
Published on

Why is my period late? It’s weird that I am aching for my ovaries to erm… ache, but when things in your body don’t seem to be doing what they’re supposed to be, it always ends in a frantic Google search to check that you’re not, you know... whispers pregnant. We all did that one in science class at school (before we skipped right past consent, the pill and masturbation, but that’s another article) where the teacher briefly explained periods before we barely had a chance to get our fluffy pencil-case out of our bags.

I am definitely not pregnant, before you ask. You can tell how single I am at any given time by my leg hair and mine currently looks like I’ve slathered on oil and skidded bare legged on the floor of the hairdressers.

Back to my late period. It’s not because I’m pregnant so what could it be? Holy insemination? Imminent Death?

Probably neither. But actually, turns out there are a whole bunch of things other than being up the duff that could cause a late period. Here are 21 of them.

**Late Period Reason #1. Weight Loss **

If you’ve lost a heap of weight, you could experience delayed or missed periods. A BMI (body mass index) of below 19 might seem ideal but if it’s happened suddenly, your body will start to panic and you may start to miss periods. Why? Because, in order to have a period you need oestrogen to build the lining of the uterus. Extreme weight loss, a low caloric intake or being very underweight stresses the hypothalamus, the gland in your brain responsible for regulating various processes in the body including your period, and your body won't release the oestrogen needed for you to have a period. In extreme cases, underweight people don’t ovulate at all. If you think weight loss could be the reason why your periods have stopped, you definitely need to see your doctor.

Late Period Reason #2. Weight Gain

On the other hand, being overweight or gaining a lot of weight in a short amount of time can cause your body to produce too much oestrogen. This may cause you to go for months without ovulating and it can cause the endometrial lining to overgrow and become unstable. This can result in heavy or irregular periods. In most cases losing few extra pounds if you're overweight should help your periods to return to normal. But if you're in anyway unsure, then again, do see your doctor.

Late Period Reason #3. Eating Disorder

Eating disorders, such as Anorexia Nervosa or Bulimia Nervosa can also cause oestrogen levels to dip too low thereby stopping menstruation.

Late Period Reason #4. Crappy Diet

Even if your weight is fairly average, a really crappy diet (i.e. Breakfast: nothing, Lunch: doner kebab, Dinner: 3 beers and a packet of fags, Midnight snack: Walkers roast chicken crisps and a Mars bar washed down with Coke) could be the cause of your late or skipped periods. A healthy diet is required for a healthy cycle so make sure your diet consists of plenty of fruit and veggies, proteins, fibre and healthy fats.

Late Period Reason #5. Excessive Exercise

Overdoing it at the gym? Yes, we know you want Jen Selter’s butt and Chloe Madeley’s abs but suddenly killing yourself at the gym when you’ve been used to just sitting on your couch scrolling their Instagram feeds, isn't always great for your body. Exercising is obviously good for you but not if you’re overdoing it. Missing a period is actually called amenorrhea (literally translated from the Greek as: “No flow”) and common sufferers are marathon runners and other endurance trainers, ballet dancers, gymnasts and other professional athletes. Bottom line: if you’re training too hard and not getting enough calories, or if you’re forcing yourself to train through injuries and sickness, your body won’t produce enough oestrogen and you might not get a period. If you slow down a little and maybe eat a bit more and train a bit less, your body should get back on track in no time. But again, see your doctor if you are in anyway concerned or unsure.

via GIPHY

Late Period Reason #6. Sickness

If you had a bad cold, the flu or any other sickness when you were ovulating, it's possible your body thought, 'no, this bird’s way too ill to have an egg,' and skipped it or delivered it later than usual. That means that your period will also arrive late or perhaps even not at all. If this was the case, it’s more than likely that next month your period will return as normal.

Late Period Reason #7. Stress

The hypothalamus, the regulating hormone, is very much affected by the stress hormones, adrenaline and cortisol. A death of a loved one, a move, a new job, a break-up, or any other life event which is causing you stress could cause your period to be a no-show or to come late. Until your brain detects that the stressful event is over, it won’t return your bodily functions to normal, and you’re just making things worse by sitting there trippin’ over where the hell your period is.

Late Period Reason #8. Change in Schedule

In addition to stress, our bodies don’t really like change. Even changing what you consider to be small things, like the time you wake up, your shifts at work, if you went travelling and changed your body clock, or if you starting a new job, your body needs some time to adjust and that can definitely affect your cycle. This is not something to worry about though because as soon as your body feels settled again, your body clock should go back to normal.

Late Period Reason #9. Hormone Problems

You may have a change in the level of the hormones which the body needs to support menstruation.

Late Period Reason #10. Thyroid Problems

The thyroid is a gland in your neck that controls hormones, regulates the metabolism and interacts with many other systems in your body to make sure everything’s in check. A thyroid irregularity such as an under-active thyroid (hypothyroidism) or overactive thyroid (hyperthyroidism) can cause changes to your period. Check with your GP to rule out any thyroid issues.

Late Period Reason #11. Pelvic Organ Problems

Granted, that’s not a very fun sentence, but pelvic organ problems are worth looking into if your period has gone MIA.

(a) Polycystic Ovary Syndrome

PCOS is a condition that can cause cysts on the ovaries and prevent ovulation from occurring regularly. It affects the hormones that release your eggs when it’s time, with the eggs remaining in the ovaries unable to be fertilised. With PCOS, your oestrogen, progesterone, and testosterone levels are out of balance. This is something that can be tested for at your GPs.

(b) Imperforate Hymen

There’s no easy way to put this. If you have an imperforate hymen, your vajayjay is literally blocked. Like, sealed over. No exit. Your period is in there, but it’s just held hostage by your hymen which is blocking off your cervix. So. Many. Questions. For one, where the hell does the blood go if it can’t get out? It actually backs up inside you and can cause infection if not treated. It can be a serious problem but, thankfully, diagnosis usually happens in the early teenage years and until this is surgically corrected (apparently pretty quickly and fairly pain-free), you are given a pill to suppress your flow.

(c) Asherman’s Syndrome

This is another “No Exit” instance where the blood would be trapped, not from your hymen, but rather, other scar tissue that has merged together and healed wonky. Again, for the most part, this condition can be fixed by surgery but you should get checked out as soon as possible.

(d) Doctor-Caused Complications

In rare instances, your doctor could be at fault. Doctor-caused complications are when you’ve had a uterus surgery (for instance, an abortion, removal of fibroids or tumours, etc.) which has caused scarring. The scarring could then block off the cervix, stopping the blood from flowing and you would need surgery to correct this.

Late Period Reason #12. Chronic Diseases

Celiac or lupus or other autoimmune diseases can throw your period off. Chronic diseases such as these usually come with a bunch or other symptoms so if a missed or late period is just yet another thing that you can add to a long list of symptoms, you really need to get yourself to a doctor and make sure to give them every single symptom you may be experiencing, from fatigue to excessive sweating, etc.

Late Period Reason #13. Other Diseases

Diabetes, irritable bowel syndrome, liver disease, tuberculosis, and other diseases can sometimes have an impact on your menstrual cycle, although a missed period is not the only, or most worrying, symptom of these diseases.

Late Period Reason #14. Other Medical Conditions

Don’t panic, but other, slightly rarer, reasons for late periods could be structural problems with the uterus, cysts or tumours (benign or cancerous). A gynaecologist will be able to check you out and let you know if you should worry about any of these.

Late Period Reason #15. Birth Control

Various contraception types can mess up your flow. Being on the pill can notoriously give you many side effects like a light flow or sometimes none at all, as can hormonal IUDs, implants, or contraceptive injections. It can also take a while for your period to come back to normal when you first stop using contraceptives.

Late Period Reason #16. Medication/Drugs

If you’ve been prescribed some new medication, or have changed the dosage of an ongoing prescription, your period can be affected. The morning after pill is also notorious for causing late periods. Other medicines that have been known to affect periods are some antidepressants, antipsychotics, antibiotics, corticosteroids and chemotherapy drugs. Taking illegal drugs can also affect your period. So have a little think about what pills you’ve been popping before panicking about your late or missed period.

Late Period Reason #17. Just Beginning to Have Periods

If you’re a spring chicken who’s just started having periods and are concerned about their irregularity, don’t worry. It’s completely normal to have late or no periods at first because your body is still trying to adjust to being a woman and get into the rhythm of things. It may even take you a few years to have regular periods but fear not, my precious! You’ll soon be doubled over in agony on a monthly basis like clockwork.

via GIPHY

Late Period Reason #18. Premature Menopause

The average age of menopause is 51. Anywhere from two to eight years before that is the perimenopausal stage where the body starts to gradually produce less and less oestrogen and moves toward menopause. Premature Ovarian Failure or Premature Menopause is when a woman stops menstruating before the age of 40. Having surgery, chemotherapy, or radiation therapy to the abdomen or pelvis can kick you into early menopause or perimenopause, as in Angelina Jolie’s case.

Late Period Reason #19. Actual Menopause

Women of around 45-55 may be approaching menopause. Ovulation gradually starts to shut down and the other organs are arranging a retirement party for the ovaries. The ovaries are all emotional but secretly looking forward to that hard earned vacation, and the other organs appear sympathetic but are secretly glad that old grumpy-pants will be out of their lives for good. After 12 months of no-show flow, menopause has officially hit.

Late Period Reason #20. Miscalculation

How do you calculate your period? Do you count 28 days from your start day? Or 3 weeks from the time you finish? Or just calculate approximately one month down the line? Have you considered the possibility that you may have miscalculated? That’s why we have period calculators, dummy! The average menstrual cycle is 28 days but some women have a 31-day cycle, and some a 27-day cycle… This can also change in each woman as the years go by. Some women even have permanent irregular cycles; 3 weeks till one period then 5 weeks for the next. Get yourself an app and start tracking your periods.

Late Period Reason #21. Breastfeeding

Prolactin, the hormone responsible for breast milk production, suppresses ovulation making it possible to not see a period for the whole time that you are breastfeeding. Periods usually come back to normal within 6-8 weeks after birth but if 3 months have passed and you’ve yet to see a period, see your doc. But you don’t need to be breastfeeding to produce prolactin. If you’re not breastfeeding (a baby) and notice that your nips are leaking, get yourself to your GP. Although it doesn’t sound very pleasant, it’s not a major problem and can usually be treated with medication.

Fun fact: You can still get pregnant even though you’re not menstruating. I repeat: You can still get pregnant even though you’re not menstruating.

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If it’s none of those, then yes; you could be up the duff.

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This article originally appeared on The Debrief.

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