My Daughter Hasn't Started Her Period Yet: Late Puberty, Late Bloomers and When to See a GP

It usually starts with a comparison. Her best friend got her period in Year 7. Her younger cousin has started wearing a bra. And your daughter — 13, maybe 14 — is still waiting, and starting to ask you, quietly, whether something is wrong with her.

If you're the parent of a so-called late bloomer, you're carrying two worries at once: hers ("why is everyone ahead of me?") and yours ("should I be doing something about this?"). This article walks through what "late" actually means, why timing varies so much, how to support her emotionally, and the specific signs that mean it's worth booking a GP appointment — usually for reassurance, occasionally for a closer look.

When do most girls start their period?

Most girls have their first period somewhere between 10 and 15, with around 12 being typical. But a first period is a late chapter in the puberty story, not the opening page. It usually arrives about two years after breasts first begin to develop, and often within a year or so of noticing vaginal discharge — the body's way of signalling that things are moving.

That's why the most useful question isn't "has her period started?" but "has puberty started?" A 13-year-old with developing breasts and no period yet is very likely right on track — her body is simply working through the earlier stages. If you'd like a map of the whole journey, our guide to the stages of puberty in girls lays out what tends to happen and in what order.

What actually counts as "late" puberty?

Doctors generally take a closer look in two situations: when there are no signs of puberty at all — no breast development in particular — by around age 13, or when there's no first period by around 15, even though other puberty signs are present. Outside those windows, "late" is usually just "later than her friends", which is a feelings problem rather than a medical one.

It's worth remembering that the normal range is wide and largely inherited. If you, her mum, or aunts and grandmothers were on the later side, there's a fair chance she's simply following the family pattern. It can be genuinely comforting for a girl to hear "I was nearly 15 too, and everything was fine."

Why might puberty or periods come later?

Often, there's no reason at all beyond genetics — late developers usually catch up completely. That said, a few everyday factors can nudge timing later. Girls who train intensively in sport or dance, or who are naturally very slim, sometimes start later because the body waits until it has enough energy in reserve. Long-term illnesses and some medicines can slow things down too. And occasionally — much less commonly — there's a hormonal reason a doctor would want to identify and treat.

None of this is something to diagnose from home, and it's certainly not something to fix with guesswork or diet changes. If the ages above have passed, or something else worries you, that's precisely what your GP is for.

How do I support a late bloomer emotionally?

For your daughter, the hard part usually isn't biology — it's the changing rooms, the sleepover chat she can't join, the feeling of being left in a younger body while friends seem to race ahead. A few things help:

Take the feelings seriously. "You're fine, stop worrying" is technically true and emotionally useless. Try "It's really hard feeling like the last one — and your body genuinely isn't behind, it's on its own schedule."

Give her the full picture. Knowledge is the antidote to the 3am "what's wrong with me" spiral. A girl who understands the stages of puberty can locate herself on the map and see she's moving, even if her friends can't tell. The When She Blooms Daughter Guide was written for exactly this — warm, factual and never patronising — and the Parent Guide gives you the words for the conversations that follow.

Prepare her anyway. Being a late starter doesn't mean being caught out. Pop a small kit in her school bag now, so that whenever the day comes she meets it with a shrug rather than a panic.

Watch your own commentary. Comments about her size, shape or "still being our little one" land harder than parents realise — even the affectionate ones.

When should we actually see a GP?

Book an appointment if any of these apply: no breast development by around 13; no period by around 15 (or by about three years after breasts began developing); puberty that started and then seemed to stall; periods that began and then stopped for several months; or significant distress, whatever her age. Go too if she has a long-term condition, trains very intensively, or has lost weight and her development has slowed.

In most cases the GP will examine her, ask about family patterns, and send you home reassured. Sometimes they'll run simple blood tests or refer to a specialist — not because something is necessarily wrong, but because it's sensible to check. Frame the visit to your daughter as "let's get some answers together", not "something might be wrong with you." (And if your worry runs in the other direction, we've also written about early puberty in girls.)

When her period does arrive, tracking it from the start helps her learn her own rhythm — the Parent–Daughter Tracker Set makes it something you can gently do together. Not sure which of our guides fits her age and stage? Take the find-the-right-guide quiz.

Frequently asked questions

My daughter is 14 with no period but has developing breasts. Should I worry?

Usually not. A first period typically follows about two years after breast development begins, so a 14-year-old with earlier puberty signs is generally on track. If nothing has arrived by around 15, or around three years after breasts began developing, check in with your GP.

Does starting late mean her periods will be irregular?

No — late starters generally go on to have the same range of cycles as everyone else. In the first year or two after any first period, irregular cycles are common and usually settle with time.

Can stress delay a first period?

Everyday school stress won't stop puberty, but significant physical stress — intensive athletic training, marked weight loss or long-term illness — can delay it. If you suspect this, it's a conversation for your GP rather than something to manage alone.

Should I talk to her about periods even though hers hasn't started?

Absolutely — earlier is easier. Girls who understand what's coming feel prepared rather than ambushed, and talking before it's personal keeps the embarrassment low. Books she can read privately are a gentle way in.