When your periods stop and you are not pregnant

Three months without a period, when you are not pregnant, not breastfeeding and not on a method that suppresses bleeding, is worth investigating. Six months certainly is. The instinct to wait and see is understandable and, past that point, not a good one — because several of the causes have consequences that accumulate quietly while you wait.

First, rule out the obvious

A pregnancy test, even if you are confident. It is the first thing any clinician will do and it costs nothing to have done it already.

Then: are you on something that stops periods? Hormonal coils, the implant, the injection, continuous combined pills and progestogen-only pills all commonly suppress bleeding, and that is a feature rather than a fault. After the depot injection specifically, cycles can take six to twelve months to return — coming off hormonal birth control has the timelines.

The four causes that account for most of it

Functional hypothalamic amenorrhoea. The signalling from the hypothalamus has switched off in response to some combination of low energy availability, high training load and psychological stress. It does not require being underweight, and it is frequently missed in people who look and feel well. This is the most common cause in otherwise healthy young people, and how stress actually interrupts your cycle covers the mechanism and the recovery.

PCOS. Chronic lack of ovulation. Usually accompanied by some androgen features — acne, hirsutism, hair thinning — and often by insulin resistance. See PCOS beyond the ovaries.

Thyroid disease. Both hypo- and hyperthyroidism disrupt cycles, and thyroid disease is far more common in women. A TSH is cheap and should be part of any workup.

High prolactin. Prolactin suppresses GnRH. It can be raised by a benign pituitary adenoma, by hypothyroidism, and importantly by medications — antipsychotics, some antidepressants, metoclopramide, and others. Milky nipple discharge is a strong clue but is often absent. This one gets missed because nobody thinks to check it.

The less common but important ones

Primary ovarian insufficiency. Ovarian function ending before 40, affecting roughly 1 percent of women. It is not early menopause in the sense of a gentle transition — it can be intermittent, and pregnancy is occasionally still possible. It requires diagnosis because the long-term consequences of low oestrogen at a young age, particularly for bone and cardiovascular health, need active management with hormone therapy. Two raised FSH levels a month apart in someone under 40 with absent periods is the usual picture.

Asherman's syndrome. Intrauterine adhesions, typically after uterine surgery such as a D&C, sometimes after infection. Periods stop or become very light despite normal hormone levels.

Late-onset congenital adrenal hyperplasia, Cushing's syndrome, and pituitary causes are all rarer but real.

What a proper workup includes

• Pregnancy test
• FSH, LH, oestradiol
• TSH
• Prolactin
• Testosterone and SHBG if androgen features are present
• Pelvic ultrasound
• Sometimes AMH, and pituitary imaging if prolactin is high

If you leave an appointment with none of these arranged and no follow-up date, that is worth a polite push. How to prepare for a ten-minute appointment has the phrasing that tends to work.

Why the wait costs something

The common thread across hypothalamic amenorrhoea and primary ovarian insufficiency is low oestrogen, and low oestrogen for months to years has consequences beyond fertility: reduced bone mineral density, unfavourable cardiovascular markers, and effects on mood and sleep. Bone is the sharpest of these, because peak bone mass is built in your twenties and not easily rebuilt later. Bone density and the years around menopause explains the mechanism.

PCOS carries the opposite risk. Very infrequent periods mean the uterine lining is exposed to oestrogen for long stretches without progesterone to oppose it, which raises the risk of endometrial hyperplasia over time. Guidelines suggest ensuring a bleed at least every three to four months for this reason.

Neither of these is an emergency. Both are reasons not to spend two years waiting.

What to bring

The most useful history is a timeline. When did periods become irregular, and when did they stop? What changed in the preceding six months — training, weight, diet, work, a bereavement, a new medication, an illness? Are there other symptoms: hair changes, acne, discharge, hot flushes, headaches, visual disturbance, weight change in either direction?

That timeline is very hard to reconstruct accurately after the fact, and it is exactly what points a clinician toward the right test first rather than third. Naked is built to keep that record as it happens — cycles, symptoms, sleep, training, mood and the life events sitting alongside them — so that when periods stop, you can show what the six months before looked like instead of guessing.

Amenorrhoea is a symptom with a short list of causes and a clear order of investigation. The main thing standing between people and an answer is usually the decision to ask.