25 weeks pregnant

How big is your baby at 25 weeks?

About the size of a courgette — around 34.6 cm (13.6 in) long head to heel, according to the NHS, weighing roughly 778 g (1 lb 11 oz).

The NHS figure jumps 4.6 cm between weeks 24 and 25, more than in any other week of the third trimester. No baby grows that fast in seven days — it is an artefact of the reference chart. Growth is smooth; the tape measure is not.

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

Hearing is now good enough to startle. The NHS describes a loud noise making your baby jump and kick — it should not hurt, but it can surprise you. You may also feel rhythmic twitches that stop after a minute or two: hiccups, and completely normal.

Your baby is passing urine into the amniotic fluid, and by now most of the liquid around them is exactly that. It cushions, keeps the temperature stable, and swallowing it is how the gut practises.

What you might feel

Puffiness in the face, hands and feet is the week 25 headline on the NHS page. Most of it is harmless water retention, but all of it is worth mentioning, because your midwife will check your blood pressure in case it is an early sign of pre-eclampsia. Swelling with a splitting headache, vision problems or pain below the ribs is not a wait-and-see situation — call the same day.

Burping, bloating, a burning chest and feeling full after very little food are indigestion, caused by your baby taking the space your stomach used to have. Smaller meals, sitting up to eat and easing off rich food are the NHS suggestions.

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 25 weeks pregnant 6 months?

Yes — week 25 is the third week of month 6.

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 — "25 weeks and 3 days" — because a few days change what is offered.

What's happening at your appointments around now

If this is your first baby, the NHS offers an appointment this week: blood pressure, urine, a bump measurement to track growth, a conversation about your baby's movements and your mental health, and your preferences for birth. If you have given birth before, the next routine appointment is at 28 weeks.

Measuring the bump — symphysis-fundal height, from pubic bone to the top of the uterus — is routine here and in Australia and New Zealand, where RANZCOG asks for it at every visit, plotted on a customised growth chart. A measurement smaller than expected usually leads to a growth scan, not to alarm.

If you are being tested for gestational diabetes you are in the window: 24 to 28 weeks in the UK and the US, 26 to 28 in the RANZCOG schedule. Being told to fast beforehand is standard.

Survival at 25 weeks

Most people reading this will never need this section. It is here because the numbers move fast now and vague reassurance helps nobody.

The BAPM framework's England and Wales data for 25-week births in 2020 to 2021: around 75 per cent of babies alive at the onset of labour survived to discharge, and around 1 in 9 survivors had a severe impairment at two years. At 24 weeks that impairment figure was 1 in 5. Each week now buys a great deal.

Those are UK figures from UK units. Thresholds and outcomes genuinely differ between countries and hospitals, which is why BAPM asks teams to counsel on a baby's individual risk profile rather than a number on a chart.

Is it safe to fly at 25 weeks pregnant?

Yes, in a straightforward pregnancy. The RCOG is unambiguous: occasional air travel is not harmful, and there is no evidence that flying causes miscarriage, early labour or your waters to break. ACOG puts the best window at 14 to 28 weeks, and notes travel gets harder after that.

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

• Three weeks until the letter requirement bites. Booking a flight for 29 weeks and asking for the letter at 28 is cutting it fine.
• 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

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