11 weeks pregnant

How big is your baby at 11 weeks?

About the size of a fig — around 41 mm (1.6 in) long from head to bottom.

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 head is still oversized but the body is catching up fast. The fingers and toes are separating out. There are tiny fingernails and miniature ears. The baby is already moving around inside the womb, though you will not feel it for several weeks.

The bigger change is on your side. The yolk sac has been feeding the pregnancy until now, and the placenta is about to take over nourishing the baby and removing waste. The hormonal handover is one reason this week can leave you tired and emotional for no obvious reason. Your body is now pumping up to 50 per cent more blood than usual, which feeds the womb and also makes many people feel hot, sweaty and dizzy.

What you might feel

Tiredness is often dominant at 11 weeks, and the NHS suggests gentle exercise such as walking genuinely helps, counter-intuitive as that sounds. Also common: aches around the lower abdomen, nausea, mood swings, a metallic taste, sore breasts, indigestion and heartburn, headaches, dizziness, changed food preferences, a heightened sense of smell, discharge, light spotting, cramping, darkened patches on the face, greasier skin, thicker hair and bloating.

Your first scan

The dating scan is offered at around 10 to 14 weeks and takes about 20 minutes. It checks how many weeks pregnant you are and sets your estimated due date, whether there is more than one baby, and that the pregnancy is developing in the right place. If you have agreed to screening, it can include the nuchal translucency measurement as part of the combined test for Down's syndrome.

Is 11 weeks pregnant 2 months or 3 months?

Week 11 is in month 3, its third week. Nearly three months 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 11 weeks

By 11 weeks the great majority of first-trimester risk is behind you. In a study of over 300 women with a history of recurrent miscarriage, seeing a heartbeat at 10 weeks gave a 99.4 per cent chance of the pregnancy continuing.

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.

Tommy's estimates early miscarriage at 10 to 20 in every 100 pregnancies overall, notes that most miscarriages happen in the first 12 weeks, and says risk goes down dramatically after 12 weeks. You are one week from that point.

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.

Tommy's makes one further observation worth knowing this week: because most people are not scanned until around 11 or 12 weeks, most reach their first scan without ever having confirmed a heartbeat. Walking in not knowing is the normal experience, not a bad sign. It is also why missed miscarriage — a loss found at a scan with no symptoms beforehand — is usually discovered at this appointment. It is uncommon, and it is not something you could have detected or prevented.

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 11 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.

The scan is the deciding factor at 11 weeks. The combined screening test has a firm window; if your scan happens after 14 weeks the NHS offers a different blood test between 14 and 20 weeks, which is not quite as accurate. Do not let a trip push your scan past 14 weeks without talking to your maternity service first.

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.

The NHS suggests mid-pregnancy, roughly 4 to 6 months, as the easiest time to travel, and ACOG names 14 to 28 weeks. You are within a few weeks of both.

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.