7 weeks pregnant

How big is your baby at 7 weeks?

About the size of a grape — around 10 mm (0.4 in) long from head to bottom. The proportions are strange and entirely correct: the brain is growing faster than the rest of the body, so the forehead is large relative to everything else. That evens out over the next couple of months.

A note on the numbers: in the first trimester babies are measured crown to rump — head to bottom, not head to heel, because the legs are curled. Weight is not reliably estimated this early, so any site quoting grams or ounces before about 14 weeks is guessing.

What's developing this week

The NHS puts a number on the brain growth that is hard to forget: the embryo is generating around 100 new brain cells every minute this week.

Alongside that, there are small dimples where the nose and ears will be. The eyelids are beginning to grow and cover the eyes. The limb buds are forming cartilage that will become the bones of the arms and legs, and the arm buds are lengthening with flattened ends that will soon be hands. Keep taking folic acid — 400 micrograms daily to at least week 12 — because the nervous system forming right now is exactly what it protects.

What you might feel

For most people week 7 is somewhere near the worst of it. Nausea, exhaustion, mood swings, a metallic taste, sore breasts, headaches, food aversions, an unwelcome sense of smell, discharge, light spotting, cramping, darkened patches of skin on the face (chloasma), thicker hair and bloating are all on the NHS list for this week.

There is a line on the NHS week 7 page worth repeating: don't ignore strange symptoms. The odds are overwhelming that an ache is ordinary pregnancy, but the way you find out is by asking. Equally, if your symptoms suddenly disappear this week, that is not automatically a warning sign.

Is 7 weeks pregnant 1 month or 2 months?

Week 7 is in month 2, its third week. Roughly a month and three weeks along in calendar terms.

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 about which month you are in. 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 — "11 weeks and 3 days" — because a few days change what is offered.

Miscarriage risk at 7 weeks

Week 7 sits just past the first evidenced milestone. Tommy's cites research showing that once a pregnancy gets past 6 to 7 weeks and has a heartbeat, miscarriage risk drops to around 10 per cent — down from the 10 to 20 per cent range that applies to early pregnancy overall.

A study of over 300 women with a history of recurrent miscarriage found a 78 per cent chance of the pregnancy continuing when a heartbeat was seen at 6 weeks, 98 per cent at 8 weeks and 99.4 per cent at 10 weeks. You are between the first two.

One caveat almost never stated: those heartbeat figures come from a study of over 300 women with a history of recurrent miscarriage, so their baseline risk was higher than average. For most people the equivalent numbers would be at least as reassuring.

You will find week-by-week miscarriage percentage tables all over the internet. Tommy's, which funds the UK's national miscarriage research centre, says openly that beyond the well-evidenced drop after 12 weeks, reliable week-by-week risk research does not really exist. We give you what is evidenced instead.

Most people have not had a scan by 7 weeks, so this is a milestone you are likely passing without confirmation. That is uncomfortable, and it is also the reality for the overwhelming majority of pregnancies that go on perfectly well.

The most common cause of early miscarriage is a chromosomal problem that happens by chance. Not lifting something, not a glass of wine before you knew, not stress or exercise. Tommy's states it directly: miscarriages very rarely happen because of something you did or did not do.

Is it safe to fly at 7 weeks pregnant?

Yes, in a straightforward pregnancy. The RCOG is unambiguous: occasional air travel is not harmful in an uncomplicated pregnancy. There is no evidence that cabin pressure or humidity harm you or the baby, and no evidence that flying causes miscarriage, early labour or your waters to break.

Week 7 is the first point at which the RCOG's advice about pre-travel scans becomes practical. If you have an increased chance of miscarriage or ectopic pregnancy, the RCOG suggests asking for an ultrasound before you fly — and from around 7 weeks a scan can usually confirm the pregnancy is in the right place and that there is a heartbeat.

The RCOG notes that most obstetric emergencies happen in the first and third trimesters, and that miscarriage in the first three months is common at around one in five whether you fly or not. Flying does not cause it. Being far from care when it happens is the thing to plan around. Pregnancy sickness compounded by motion sickness is still the practical problem at 7 weeks.

The risk that is real: blood clots

Pregnancy raises deep vein thrombosis (DVT) risk from the earliest weeks. 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, comfortable shoes, an aisle seat, regular walks about the cabin
• In-seat exercises roughly every 30 minutes
• Water steadily; cut down on caffeine
• Graduated compression stockings — not ordinary flight socks, and sized for you by a midwife or doctor

With other clot risk factors you may be advised to have heparin injections around the flight.

Practical points

• No airline restricts travel this early — cut-offs sit around 36 to 37 weeks for one baby, 32 for twins.
• Check what maternity and emergency care exists at your destination.
• Tell your insurer you are pregnant; cover should include pregnancy-related care.
• Some travel vaccines and anti-malarial tablets are unsuitable in pregnancy; travel to Zika areas is not recommended.

When to call your midwife or doctor

Early pregnancy is full of sensations that turn out to be nothing. These are the ones worth a phone call.

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 bleeding with any of the following, which the NHS lists as needing immediate assessment:

• Severe abdominal pain you cannot concentrate through
• Pain in the tip of your shoulder
• Feeling sick, faint or dizzy, or losing consciousness
• Heavy bleeding that soaks through a pad quickly

Sudden sharp abdominal pain with dizziness, faintness or looking very pale can indicate a ruptured ectopic pregnancy, needing same-day surgery. Around 1 in every 90 UK pregnancies is ectopic, and the NHS notes symptoms usually appear between weeks 4 and 12 — where you are now.

Call your midwife, early pregnancy unit or health line today

• Light bleeding or spotting, with mild or no pain
• One-sided pain low in your abdomen or pelvis
• Brown, watery discharge that is new for you
• Pain when you pee or open your bowels
• You cannot keep food or fluid down for 24 hours, your urine is very dark or absent for 8 hours, you feel severely weak or faint, or you are vomiting blood or losing weight — the NHS triggers for pregnancy-sickness help, which is treatable

You do not need a booking appointment first, and you do not need to be certain something is wrong.