Missing a period is typically a big red flag (or lack thereof) of one thing: pregnancy.
However, bodies are complex things, and there are a number of reasons you might find yourself with an unexpected surplus of tampons and paracetamol.
For most of us, an absent period is a once in a blue moon occurrence—usually as the result of emotional strain, or lifestyle changes, and passes without much cause for concern.
Yet in some women, amenorrhoea—the medical term for skipping a period for an extended stretch of time—can happen for months, or even years, and the circumstances may be entirely out of their control.
There are two types of amenorrhoea. The first is primary amenorrhoea, when you haven't started your period by the age of 16, or 14 if you're not showing any other signs of puberty.
Secondary amenorrhea is defined by the disappearance of your periods for at least six consecutive months if you usually have regular bleeds, or a year if you typically bleed less frequently than every six weeks.
Dr. Virginia Beckett, spokesperson for the Royal College of Obstetricians and Gynaecologists, says that (aside from the obvious bun in the proverbial oven) the common causes of a skipping periods are:
2. Sudden weight loss
3. Being overweight or obese
4. Extreme over exercising (the American Fitness Professionals & Associates estimates that up to 45% of female athletes experience menstrual irregularity)
5. Taking the contraceptive pill
6. Reaching the menopause
7. Polycystic ovary syndrome
It makes sense that your body has certain physical requirements to maintain your normal cycle. For instance, the National Health Service points out that losing too much body fat, through intense exercise or otherwise, can stop you from ovulating. But the factors that cause amenorrhea are incredibly varied, and can be connected to a number of different health conditions.
"Periods may also sometimes stop as a result of a long-term medical condition, such as uncontrolled diabetes, an overactive thyroid, or premature ovarian failure," Virginia explains. Premature ovarian failure is early menopause, which can happen at a much younger age than you might expect (the youngest reported cases have happened to girls in their teens).
If you've missed three periods in a row, and you're definitely not pregnant, Virginia recommends seeking medical advice, but don't freak out—it's not always because you have a reason to be worried. Sometimes, your amenorrhoea could be related to something as simple as the tablet that thousands of us take each day.
"Women might miss a period every so often if they're taking birth control pills. This isn't usually a cause for concern," she assures. "Some types of contraception, such as the progestogen-only pill, contraceptive injection, and intrauterine system (IUS), particularly Mirena, can cause periods to stop altogether. However, a woman's periods should return when she stops using these types of contraception."
On the other hand, if your periods have stopped because of major changes to your weight or eating habits, this can be a reflection of more serious future problems, including osteoporosis and fertility issues.
"If a woman's periods stop due to weight loss or diet, this can have an impact on bone density which may affect health in the long term," Virginia explains. "In some cases, this may cause a permanent hormonal imbalance which can have implications for fertility."
"In some women, periods never resume naturally. This may respond to treatment or lifestyle changes but some women may be diagnosed with premature ovarian insufficiency, requiring hormone replacement therapy or perhaps donor eggs if pregnancy is desired. Women should also see a doctor if their periods stop before they're 45 or if they're still bleeding after 55."
If you have amenorrhea, your doctor may recommend waiting to see if your periods return on their own. In other cases, you may need treatment—some women are referred to gynecologists or endocrinologists to investigate their symptoms further.
Ultimately, the type of help you'll receive depends on what's causing your amenorrhea—but the most important thing is asking for help in the first place.
If you have any fears about any aspect of your health, you should contact a healthcare professional directly for tailored advice and support.
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This article originally appeared on Cosmopolitan.com/uk. Minor edits have been made by the Cosmo.ph editors.