Missed periods aren't the most fun. Most of you have been there: You notice your period is days late and immediately jump to the conclusion that you're pregnant. Even if you've not had sex in the last nine months and it literally would have had to happen by immaculate conception.
From there it's mainly panic buying as many pregnancy tests as your hands can physically carry, costing you a whole lot of money and unnecessary stress in the process.
But we've got news for you: A late or missed period doesn't necessarily equal pregnancy. I mean, sometimes it does. But the absence of your monthly friend could be down to a myriad of different reasons you might not be aware of. Dr Clare Morrison, GP at MedExpress, talks us through what they could be.
1. Exercising too much
Working out is great for you, but exercising too much can have detrimental effects on your body in the short-term. If you're pushing yourself too hard, spending every waking moment at the gym, your body can struggle to produce enough oestrogen to complete its menstrual cycle, resulting in missed periods.
Gymnasts, professional athletes and dancers are at greater risk for a condition called amenorrhea, which is where you miss your period for at least three months in a row.
2. Your weight
A dramatic change in weight, like being too underweight or overweight, can prevent your period some months. Your weight can affect a gland in your brain which is responsible for regulating some of the processes your body usually has, including your menstrual cycle.
Paramount weight loss, a really low caloric intake and being underweight makes the body unable to release oestrogen which is needed to build the lining of the uterus. This also happens with eating disorders such as bulimia and anorexia nervosa.
Being overweight can also prevent a period but this is due to the body producing too much oestrogen. This leads to the endometrial lining to overgrow which causes it to become unstable which initially results in heavy periods but could then lead months going without one.
Everyone feels stressed out sometimes, but did you know that it could actually prevent your body from having a period?
Stress due to an emotional break up, a busy job or a troubled home life can cause something called hypothalamic amenorrhea, which is when an area of your brain where hormones for your period are regulated starts to not perform properly. This can cause late or completely missed menstruation.
A simple illness such as a cold or something more serious could actually prevent you from getting your period. Your body may have to decide what functions are the most important until the illness has vacated your body, which could mean that it sacrifices your menstrual cycle to battle the infections and keep you as healthy as possible.
5. A change in lifestyle
This can go hand in hand with stress but something as simple as moving house, changing hours at work, travelling or waking up earlier can lead to a skipped period. These changes can interfere with your body clock, which helps to regulate your hormones.
This will only usually cause one skipped period, if it causes any at all, as once your body gets used to the new schedule, the menstrual cycle will return to normal.
One of the most common reasons to miss a period or multiple periods is down to medication such as birth control. Some hormone contraceptives, like the pill or the injection work by preventing the body from ovulating which of course leads to no periods. These methods don't necessarily mean you won't bleed at all while you are taking them; some people will still experience irregular bleeding or a normal period if you are on the combined pill.
Other medications which can prevent or delay your menstrual cycle include antidepressants, chemotherapy drugs and antipsychotics.
7. Polycystic Ovary Syndrome
Polycystic Ovary Syndrome (PCOS) is a condition which affects how the ovaries work. Polycystic ovaries contain a number of follicles which are under developed sacs wherein eggs develop. The problem is, these sacs are usually unable to release eggs which means ovulation doesn't take place.
It is thought that PCOS affects one in five women in the UK although it's difficult to know exactly how many have the condition. Other symptoms you may have PCOS include difficulty getting pregnant, excessive hair growth, thinning hair or even hair loss, acne and weight gain.
8. Premature menopause
Some women will go through something called premature menopause which will prevent them from getting periods for the rest of their life. Premature menopause is where a woman under the age of 40 experiences all the symptoms of menopause including stopping having a period and being unable to get pregnant naturally.
This can be caused by genetics, illness or even medical procedures.
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This article originally appeared on Cosmopolitan.com/uk Minor edits have been made by the Cosmo.ph editors.