Week 12 of pregnancy: End of First Trimester

On this site, week 12 is the last week of the first trimester. Your baby has all its major organs and limbs, and the job from here is mostly growth. Many people have a dating scan around now, often combined with the NT scan and double marker, which confirms how far along you are and how many babies there are. The chance of miscarriage has fallen considerably, though it is not zero, and nausea is lifting for many. It is also when many people start thinking about sharing their news.

The NHS gives an average crown–rump length of about 5.4 cm at 12 weeks, with a typical range of roughly 4.5–6.5 cm; the 14 g weight is an estimate. If the scan measurement does not match your period dates, it is usually the due date that is adjusted, not a sign that the baby is too big or small.

Every pregnancy is different - you may have some, all or none of these.

Nausea easing

Many people notice fewer bad days as hCG levels fall. If you are still being sick often, it does not mean something is wrong, but tell your doctor, because treatment is available. If you cannot hold down even water, get help the same day.

Returning appetite and lingering aversions

Tastes may change again as nausea lifts, while some aversions linger. Eat what you can manage and fill the gaps gradually.

Tight waistband

Your growing uterus plus a slower gut can make clothes feel snug. Elastic waistbands and looser clothes are more comfortable than tight belts.

White vaginal discharge

A thin, white, mild-smelling discharge is normal in pregnancy and nothing to treat. If it becomes itchy, smelly, green, yellow or watery, tell your doctor, as it may need checking for infection.

• Dating scan

  Commonly offered

  Often 11–14 weeks; UK 11+2 to 14+1 weeks

  Measures crown–rump length to confirm how many weeks pregnant you are and set your due date, checks the heartbeat and shows how many babies there are. It is routine in the UK; in India it is commonly done privately, often with the NT scan. If it shows twins, your doctor will explain what that means for your care.

• First visit deadline (India)

  Routine

  Within 12 weeks

  Government guidance is that every pregnant woman should be registered and seen at least once by 12 weeks. If you have not been seen yet, go to your nearest health centre or doctor this week. The next visit window runs from 14 to 26 weeks.

• Low-dose aspirin

  Only if needed

  From 12 weeks, only if advised

  In the UK and US, people at higher risk of pre-eclampsia may be prescribed low-dose aspirin from 12 weeks. It is a preventive medicine, quite different from aspirin as a painkiller, so never start it yourself; if prescribed, take it exactly as advised.

• Folic acid, then iron-folic acid

  Routine

  Folic acid usually until the end of 12 weeks

  Standard advice is to take folic acid through the first 12 weeks. From the second trimester, India's programme moves on to a daily iron-folic acid tablet, which your doctor, ANM or health centre will give you.

The exact timing of the dating scan and first-trimester screening depends on where you receive care. If your scan is booked for later than 13+6 weeks, ask whether screening will still be possible.

• 🌿Extra calories are not needed yet; that changes from the second trimester. As your appetite comes back, focus on the quality of what you eat rather than the quantity.
• 🌿Make whole grains your everyday base: whole-wheat, jowar, bajra or ragi roti, brown or hand-pounded rice, daliya, oats and poha give more fibre and steadier energy than maida, white bread or biscuits.
• 🌿Millets fit easily into familiar dishes, such as bajra roti, ragi dosa, jowar upma or a millet khichdi with dal and vegetables.
• 🌿If cravings for sweets or fried snacks return with your appetite, keep them occasional; India's dietary guidelines advise keeping added sugar low in pregnancy.

• •After the first trimester, try to avoid long spells lying flat on your back or standing still, because the uterus can press on large blood vessels and make you feel dizzy or sick. Brief periods are unlikely to harm; if you feel unwell, turn onto your side.
• •Adapt yoga or floor exercises by doing them side-lying or propped up on cushions or a wedge.
• •If your energy is returning, this is a good time to build towards regular activity on most days.

• •When to share your news is your choice. Many people wait until after the dating scan; others tell close family earlier so they have support. There is no right time.
• •If you work, think about when to tell your employer, especially if your job involves heavy lifting, long hours on your feet or chemicals, so adjustments can be made.
• •Update any pregnancy app or calendar with the due date from your dating scan so later tests are timed correctly.
• •If you have had a miscarriage before, tell your doctor so your care can be planned with that in mind.

• ?Has the dating scan changed my due date?
• ?Did the scan show one baby, and is everything as expected for this stage?
• ?Am I someone who should take low-dose aspirin?
• ?When should I stop folic acid and start iron and calcium tablets?
• ?When is my next visit, and what will happen at it?

• Note your confirmed due date
• Finish your folic acid course as advised
• Decide who you want to tell, and when
• Swap one refined-flour snack a day for a whole-grain option
• Ask when your next appointment is due