Week 31 of Pregnancy: What to Expect

Health information for learning and planning — not medical advice, and not a substitute for your own clinician.

Clinician reviewedLast reviewed Aug 19, 2026

Week 31 is when position starts to be checked properly, and when the word breech first comes up for some women. It is early for that word to mean much. There is a final growth spurt still to come for both of you.

Your body this week

In a first pregnancy, a midwife or doctor will usually measure the size of the womb around now, from the top of the pubic bone to the top of the bump, and feel the abdomen to work out which way up the baby is.

Some babies are head down already, and some have not moved into the pelvis at all — the NHS notes that some do not engage until labour starts. Being head up at 31 weeks is not a plan for a caesarean; it is a position on one day.

If a baby stays head up as term approaches, that does change the options discussed, and there are ways to encourage a turn. That conversation belongs to weeks 36 and 37 rather than to this one.

What you may notice

Braxton Hicks contractions often start around now: the bump tightening for 20 to 30 seconds and then relaxing. The NHS describes them as painless practice contractions, and adds the line that matters — if they become painful or come at regular intervals, contact a midwife or maternity unit.

Alongside them: sleep problems, stretch marks, sore gums, round ligament pains, piles, headaches, backache, indigestion and heartburn, bloating and constipation, leg cramps, feeling hot, dizziness, swelling, and skin and hair changes.

Your baby this week

Around week 31, the length given is about 41.1cm from head to heel, which the NHS compares to a coconut. Population figures, not a measurement of any one pregnancy.

There is a lot of activity — moving, finger-sucking, the occasional somersault. Fat is filling out the skin, the volume of amniotic fluid is increasing, and voices from outside are becoming recognisable.

What care usually happens around now

In the UK, women expecting a first baby are usually offered an appointment at around 31 weeks: blood pressure, urine, bump measurement, and the results of any tests from the 28-week visit. Women who have had a baby before typically go from 28 weeks to 34.

This is also when feeding usually gets discussed. ACOG and the NHS both describe the benefits of breastfeeding, and both are clear that not everyone can or will, and that formula feeding with plenty of contact is a good start too. Breastfeeding in the first two weeks covers the practical side. Schedules and antenatal classes differ between countries.

This week's tip

Ask what your bump measurement was, in centimetres, and write it down. It is measured at most appointments from now on, and the useful information is not one number but the trend across several — which nobody can show you if the earlier ones were never recorded anywhere you can see.

When to see a doctor

Contact your maternity service the same day for reduced movements, leaking fluid, painful or regular tightenings, or bleeding. Pregnancy warning signs has the full list.

Seek care now: Contact your local emergency services or go to your nearest emergency department if you have heavy bleeding, severe or one-sided tummy pain, a severe headache with vision changes, sudden swelling of the face or hands, a fever, fluid leaking from the vagina, chest pain, trouble breathing, fainting, or a seizure. Contact your maternity service the same day for any reduction in your baby's usual pattern of movement. Femio cannot assess a pregnancy.

Frequently asked questions

The baby is breech. Does that mean a caesarean?

Not at 31 weeks. There is time to turn, some babies do not settle into position until labour, and if a baby is still breech at around 36 weeks there are options to discuss then.

How do I tell Braxton Hicks from real contractions?

Practice contractions tighten and release and should not hurt. Week 32 covers position again, and week 30 covers the stages of labour. Regular or painful tightenings are a call, whatever you think they are.

Sources

This is general wellness information, not a substitute for professional medical advice.

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If you may act on thoughts of harming yourself or someone else, or you are in immediate danger, contact the emergency services available where you are now or go to the nearest emergency department.

If you can, stay with someone you trust while you get help.

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If you are worried about someone else

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31 Weeks Pregnant: Position, Size and Breech — Femio