33 weeks pregnant

How big is your baby at 33 weeks?

About the size of a pineapple — around 43.7 cm (17.2 in) long head to heel, according to the NHS, weighing roughly 2,103 g (4 lb 10 oz).

Your baby has passed 2 kg and will roughly gain another 1.5 kg before a term birth.

A note on the numbers: from week 20 the NHS measures head to heel, not head to bottom. Weights here are the median of the WHO fetal growth charts — half of babies weigh more, half less, and a scan estimate can be out by 10 to 15 per cent either way. A number below the median is not a diagnosis.

What's developing this week

The brain and nervous system are now fully developed.

The bones are hardening — with one deliberate exception. The skull bones stay soft and separated, and will remain so until your baby is around 12 to 18 months old. That flexibility is what lets the head mould and make the journey down the birth canal.

Everything else from here is weight: the last few weeks are about fat, not construction.

What you might feel

Braxton Hicks. The NHS describes them as your uterus preparing for birth: a tightening across your bump lasting 20 to 30 seconds before the muscles relax. They should not hurt.

Braxton Hicks or real contractions?

The NHS says Braxton Hicks generally do not last long, do not happen frequently, and do not build up. Real contractions get longer, stronger and more frequent. ACOG adds a practical test: false contractions have no pattern, do not get closer together, are weak and do not get much stronger, and often stop if you rest, drink water or change position. True labour contractions come at regular intervals, get closer together, each last around 60 to 90 seconds, and carry on whether you rest or move.

If tightenings become painful or come at regular intervals, contact your midwife or hospital — you are 33 weeks, and labour before 37 weeks is premature labour. Our contraction timer gives you the length, the gap and the pattern to read down the phone; it does not tell you whether you are in labour.

There is no target number of movements: the NHS is explicit that you do not need to count kicks. What matters is your baby's usual pattern, and calling immediately if it reduces, weakens or changes. Our kick counter describes a pattern; it does not score one.

Is 33 weeks pregnant 8 months?

Yes — week 33 is the second week of month 8. Seven weeks to your due date, though only 1 baby in 20 arrives on it.

There is no official weeks-to-months map. A calendar month averages about 4.3 weeks, not 4, so 40 weeks is a little over nine months, and two apps can disagree. The most widely used mapping:

• Month 1 — weeks 1 to 4
• Month 2 — weeks 5 to 8
• Month 3 — weeks 9 to 13
• Month 4 — weeks 14 to 17
• Month 5 — weeks 18 to 22
• Month 6 — weeks 23 to 27
• Month 7 — weeks 28 to 31
• Month 8 — weeks 32 to 35
• Month 9 — weeks 36 to 40

Your maternity team will not use months. Everything is booked by week and day — "33 weeks and 3 days" — because a few days change what is offered.

What's happening at your appointments around now

No routine UK appointment at 33 weeks; the next is at 34 weeks for everyone. Three things are worth doing in the gap.

Pack a bag. The NHS suggests getting one ready now: your birth plan and maternity notes, clothes and nappies for the baby, something loose to wear in labour, spare clothes and underwear, nightclothes, nursing bras and breast pads, very absorbent sanitary pads, a wash bag and towels, snacks and any medicines. Our hospital bag checklist covers the rest.

Store the numbers. The NHS asks for these in your phone and written down: your midwife or hospital, your hospital reference number, your birth partner, the full address of where you are going, and a taxi firm or someone who can drive — because you should not drive yourself.

Ask about group B strep. Up to 2 in 5 people carry this common bacterium harmlessly. In pregnancy there is a small risk it can make a baby seriously ill, and the NHS says most newborn group B strep infections are preventable. The UK does not screen everyone routinely; several other countries do. Ask what happens where you are giving birth.

If you missed the whooping cough vaccine, the NHS asks for it before week 33 — and if you are past that, have it anyway.

Is it safe to fly at 33 weeks pregnant?

Medically, in a straightforward single pregnancy, the RCOG still says the safest time to fly is before 37 weeks. Practically, this is late. ACOG considers travel after 28 weeks riskier and advises a check-up 4 to 6 weeks before any trip. With twins you are past the RCOG's 32-week mark.

Keep two things apart. The medical position is the RCOG's: the safest time to fly is before 37 weeks with one baby and before 32 weeks with uncomplicated twins, because from those points labour becomes likely. The airline position is a commercial rule — most carriers refuse you after 37 weeks, some set an earlier limit, and from 28 weeks most want a letter from your midwife or doctor, which the NHS warns can cost money and take weeks. An airline rule is not medical advice.

The risk that is real: blood clots

ACOG puts it plainly: any travel of four hours or more — car, train, bus or plane — doubles DVT risk, and pregnancy adds to that. Under four hours the RCOG says you are unlikely to need special measures. Over four hours:

• Loose clothing, an aisle seat, regular walks about the cabin
• In-seat exercises roughly every 30 minutes, and water steadily
• Graduated compression stockings sized for you by a midwife or doctor — ACOG warns that stockings which are too tight or worn wrongly increase the risk instead

Practical points

• Check that your insurance covers premature birth abroad and neonatal care, not just your own treatment. The NHS names this specifically.
• Check what maternity and neonatal care exists at your destination, and carry your maternity notes.
• Tell your insurer you are pregnant. The NHS says cover should include care in labour, premature birth and the cost of changing your return date.
• Travel to Zika areas is not recommended; some travel vaccines and anti-malarials are unsuitable.

When to call your midwife or doctor

Maternity units are staffed 24 hours a day, and away from home you can walk into any of them.

Get emergency help now

Call your local emergency number (999 in the UK and Ireland, 911 in the US and Canada, 000 in Australia, 111 in New Zealand) or go to an emergency department if you have:

• Heavy vaginal bleeding, or bleeding with severe abdominal pain
• Abdominal pain you cannot concentrate through
• Fainting or collapse, chest pain, or sudden breathlessness
• A severe headache painkillers do not touch, blurred vision or flashing lights, pain below your ribs, vomiting, or sudden swelling of your face, hands or feet — NHS and ACOG both list these as pre-eclampsia symptoms needing immediate assessment
• Pain, swelling or heat in one calf or thigh, which can be a DVT

Call your midwife or maternity unit today, whatever the hour

• Any reduction, weakening or change in your baby's usual pattern of movements. Call immediately, not in the morning, and do not use a home doppler — hearing a heartbeat does not mean your baby is well
• Regular tightenings, period-type pains, or backache that is not usual for you — the NHS list for possible premature labour, meaning labour before 37 weeks, which affects about 8 in every 100 babies
• A gush or a trickle of fluid, which could be your waters breaking
• Any vaginal bleeding, however light
• Itching without a rash, especially at night or on your palms and soles — it can be intrahepatic cholestasis of pregnancy
• A temperature, feeling generally unwell, or burning when you pee
• Tightenings that become painful or come at regular intervals — the NHS asks you to call in case you are going into labour

You do not need to be certain something is wrong. That is what the number is for.