You are ten days from your last period and there is a smear of brown on the liner. Nothing else. It is gone by tomorrow. Then it happens again next month, and now you are wondering whether it means anything.
Usually it means your estrogen is fluctuating and your uterine lining is unstable, which is the ordinary business of perimenopause. Sometimes it means something structural that is worth finding. The pattern is what separates the two.
This article is for informational purposes only and is not medical advice. Bleeding changes have many causes, and only your healthcare provider can evaluate yours.
Why spotting happens during the transition
The uterine lining is maintained by a fairly steady estrogen signal. In perimenopause that signal stops being steady — it climbs, drops abruptly, climbs again. Each sharp drop can cause a small part of the lining to break down and shed, outside any normal cycle.
The common hormonal causes are:
- Estrogen dips mid-cycle. A brief fall around ovulation is enough to produce a day of light bleeding.
- Cycles without ovulation. Without progesterone the lining thickens unevenly and sheds in patches rather than all at once.
- A lining that has outgrown its blood supply. Prolonged estrogen exposure builds a thick lining whose outer layers become fragile.
Causes that are not hormonal
These are common, benign and worth identifying, because most are straightforwardly treatable:
- Endometrial polyps. Soft overgrowths of the lining, highly prone to bleeding between periods. Frequently the culprit when spotting is regular and predictable.
- Fibroids. Particularly those sitting within the uterine cavity.
- Cervical changes. A cervical polyp or an inflamed cervix bleeds readily on contact, which is why bleeding after sex is treated as its own signal.
- Vaginal dryness. Thinning tissue from falling estrogen can bleed with friction. This tends to be bright red, immediately after sex, and small in volume.
- Contraception and hormone therapy. Breakthrough bleeding is expected in the first months on a new hormonal method or a new HRT regimen, and usually settles.
- Infection. Less often, but it belongs on the list, especially with discharge or pain.
Which spotting to get checked
| Feature | Usually hormonal | Worth investigating |
|---|---|---|
| How often | Now and then, no fixed pattern | Every cycle, several cycles running |
| Amount | A liner at most | Enough to need a pad |
| Timing | Mid-cycle, or just before a period | Straight after sex, every time |
| With it | Nothing else | Pain, unusual discharge, fever |
| Your stage | Still having periods | 12+ months without one — always |
Describing it usefully
Spotting is remarkably hard to recall accurately a month later. Was it three days or one? Before the period or after? Brown or red? Those details genuinely change what a clinician suspects — bleeding reliably at the same point each cycle points somewhere quite different from bleeding at random.
Four things are worth noting at the time: the date, how many days into your cycle it was, the colour, and roughly how much. That is enough to show a pattern across three cycles, which is usually what an appointment needs.
What evaluation involves
For repeated intermenstrual bleeding, expect an examination including a look at the cervix, a pelvic ultrasound to check for polyps and fibroids and to measure the lining, cervical screening if it is due, and sometimes a hysteroscopy — a thin camera passed into the uterus, which can find and remove a polyp in the same visit. A lining biopsy is added where the lining is thickened or risk factors are present.
The Bottom Line
Spotting between periods is a common feature of perimenopause, driven by an estrogen signal that has stopped being steady. Occasional light spotting with no other symptoms is usually hormonal. Spotting that repeats over several cycles, follows sex, needs more than a liner, or happens after a year without a period is worth investigating — usually turning up a polyp or fibroid that can be dealt with. Recording the date, the colour and the amount as it happens is what turns a vague impression into something your doctor can work from.