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Key Takeaways
- Amenorrhoea often signals an underlying issue such as hormonal imbalance, stress, excessive exercise, or an underlying medical condition.
- If your period has stopped for three months (or six months if your cycles are usually irregular), it's important to seek medical assessment.
- Identifying the underlying cause helps guide appropriate care and can protect your long-term reproductive and overall health.
Your period has stopped. You’ve ruled out pregnancy. You’ve told yourself it’s stress — and sometimes, that may be true.
But when three months pass, then six, a missed period starts to feel less like a pause and more like a sign that something in your body needs attention.
Knowing the cause matters, because the next step may be simple reassurance, lifestyle changes, or specialist treatment.
What is amenorrhoea?
Amenorrhoea is the absence of menstrual periods in a woman of reproductive age. It is not a diagnosis in itself – it is a symptom of something else. The underlying cause determines how serious it is and what treatment, if any, is needed.
Amenorrhoea is usually divided into two types.
Primary amenorrhoea means a period has never started. Doctors usually investigate if menstruation has not begun by age 15 despite normal puberty, or by age 13 if there are no signs of puberty.
Secondary amenorrhoea means periods stop after they have already started. This is commonly defined as three missed periods in someone whose cycles were previously regular, or six months without a period in someone whose cycles have always been irregular.
Pregnancy should always be ruled out first, since it is the most common cause of a missed period.
Why does your period stop?
Amenorrhoea is usually grouped into a few broad categories. That makes it easier to narrow down the cause and decide which specialist may be most helpful.
Hypothalamic amenorrhoea
Hypothalamic amenorrhoea happens when the brain reduces the hormonal signals that trigger ovulation. This can happen with low body weight, rapid weight loss, intense exercise, inadequate food intake, and sustained physical or psychological stress.
PCOS and hormonal causes
PMOS or Polyendocrine Metabolic Ovarian Syndrome (previously known as PCOS) is another common cause of secondary amenorrhoea. In PMOS, hormone imbalance disrupts regular ovulation, so periods may become infrequent, irregular, or stop altogether. Thyroid disorders and raised prolactin levels can also disrupt the cycle.
Structural causes
Structural causes are less common, but important to consider, especially in primary amenorrhoea or after a uterine procedure. These include Asherman syndrome, which involves scar tissue inside the uterus, and imperforate hymen, which can block menstrual flow.
Which women are more likely to develop amenorrhoea
Common risk factors for amenorrhoea
Not every woman with amenorrhoea can identify a clear reason why their periods have stopped. However, certain factors make it more likely and can help explain changes in the menstrual cycle.
You may have a higher risk of amenorrhoea if you:
- Have lost a significant amount of weight in a short period or are underweight.
- Exercise intensely without eating enough to meet their body's energy needs.
- Experience ongoing emotional stress or physical stress from illness or demanding lifestyles.
- Have an eating disorder, such as anorexia nervosa.
- Have a family history of conditions such as PMOS, early menopause, or amenorrhoea.
- Have recently stopped using certain hormonal contraceptives, particularly contraceptive injections, as periods may take several months to return.
- Have had uterine surgery, dilation and curettage (D&C), or pelvic infections, which can sometimes lead to scarring inside the uterus.
- Have long-term medical conditions such as thyroid disorders, diabetes, or autoimmune diseases that affect hormone balance.
Some women may not fit the typical picture. For example, women who maintain a healthy weight but exercise regularly, have demanding work schedules, or experience ongoing stress can also develop amenorrhoea. Likewise, some women with PMOS may not be overweight.
Because different conditions can cause similar symptoms, a medical assessment is important to identify the underlying reason and recommend appropriate treatment.
Symptoms that may accompany amenorrhoea
The main symptom of amenorrhoea is the absence of menstrual periods. Depending on the underlying cause, you may also notice other symptoms that provide clues about what is affecting your menstrual cycle.
While these symptoms can provide important clues, they do not confirm the cause of amenorrhoea. A medical assessment, which may include blood tests or imaging, is often needed to identify the underlying reason and guide appropriate treatment.
When to see a doctor and which specialist you need
If your period has stopped, don’t wait too long to get it checked. For primary amenorrhoea, see a doctor if your period has not started by age 15, or by age 13 if puberty has not begun. For secondary amenorrhoea, medical review is usually recommended after three missed periods if your cycles were previously regular, or after six months if your cycles were always irregular.
You should be seen sooner if amenorrhoea comes with other symptoms such as acne, new facial or body hair, unexplained weight gain, milky nipple discharge, hot flushes, or vaginal dryness. These can point to specific hormonal causes that need earlier investigation.
In most cases, the right first specialist is a gynaecologist. If the pattern suggests PMOS, thyroid disease, prolactin problems, or another endocrine issue, an endocrinologist or reproductive endocrinologist may also be involved. If hypothalamic amenorrhoea is linked to low intake, weight loss, or heavy exercise, a dietitian can be a useful part of the care team.
Seeking medical advice early can help diagnose the underlying cause and support timely treatment
How is amenorrhoea diagnosed?
Diagnosis starts with your medical history and a physical examination. Your doctor will usually ask about menstrual patterns, weight changes, exercise, stress, medication use, and any other symptoms you have noticed. A pregnancy test is usually done early.
Blood tests often include FSH, LH, prolactin, oestradiol, testosterone, and thyroid function tests. If PMOS is suspected, blood glucose or insulin-related testing may also be considered.
A pelvic ultrasound can help assess the uterus, ovaries, and uterine lining. MRI may be used if a pituitary or hypothalamic cause is suspected. In some cases, further tests such as chromosomal analysis or hysteroscopy may be needed.
How is amenorrhoea treated?
Treatment depends on what is behind the missed periods. In many cases, the goal is to correct the underlying issue so that your cycle can return naturally.
For some people, that means improving nutrition, adjusting exercise, reducing stress, or making other lifestyle changes that support regular ovulation. Others may need hormone-based medication, medicines for thyroid or prolactin-related problems, or treatment for a condition affecting the uterus or pituitary gland.
In some cases, medicine is used to protect the uterine lining, support hormone balance, or help restore ovulation. Surgery is only needed in selected cases, such as when there is a structural problem or another issue that cannot be managed with medication alone.
Can amenorrhoea be prevented?
Amenorrhoea cannot always be prevented, especially when it is linked to underlying medical conditions. But in some cases, supporting your body with enough nutrition, avoiding extreme calorie restriction, matching exercise to your energy intake, and managing ongoing stress may help lower the risk of cycle disruption.
It also helps to keep track of your menstrual cycle. If your periods become irregular or stop, noticing the change early makes it easier to get the right diagnosis and treatment.
How can HiA help?
If your period has stopped and you are not sure what to do next, HiA can help you make sense of the next step before you book an appointment. That includes helping you understand whether a referral is pointing you to the right specialist for your symptoms, not just the nearest available doctor.
For amenorrhoea, the right specialist depends on what may be driving the change. Some people need a gynaecologist first, while others may be better served by an endocrinologist or reproductive specialist. HiA helps match you to the most relevant doctor based on your symptoms, medical history, and likely cause.
Frequently asked questions
Yes, physical or emotional stress can affect the hormone signals that control ovulation, which may delay or stop your period. But stress should not be assumed to be the only reason without checking for other causes.
Not always. A single late period can happen for many reasons and may settle on its own. If the pattern keeps happening, or your period stops completely, it is time to get it assessed.
It can, because periods often stop when ovulation is disrupted. But the effect on fertility depends on the underlying cause, and many people can still be treated once the reason is identified.
Disclaimer
This article and its contents are provided for educational and informational purposes only and do not constitute medical advice or professional services specific to you or your medical condition. For decisions about your health or treatment, speak with a qualified doctor who knows your situation. An…
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