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Week 12

Your baby is now about the size of a plum, and hopefully you are starting to feel much better as the 1st trimester comes to a close.

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What's happening in my body?

There's a good chance that the placenta is now feeding your baby, having taken over from the yolk sac, and once this happens your hormones will calm down a bit.

Your waist is probably thickening and your breasts getting bigger. As the sickness subsides, you may start to feel hungrier and worry if you're eating enough for you and the baby.

You may wonder if your bump should look bigger or smaller. There are so many factors that determine how big your stomach gets including:

  • your hormones
  • pre-pregnancy weight
  • how many babies you've already had
  • the strength of your muscles

Gaining weight and eating during pregnancy

Many women worry about how much weight they should put on during a healthy pregnancy.

Most mums-to-be will put on between 10kg and 12.5kg (22lb to 26lb), and that's usually after week 20. But some may not put on any weight at all.

You can find out more about weight gain in pregnancy on the NHS website.

Try to follow a healthy pregnancy diet – you do not need to eat more for the baby. When you enter the 3rd trimester in week 28 you can add another 200 calories a day to your diet – that's about 2 slices of wholemeal toast with margarine.

If you maintain a healthy weight, your baby is more likely to be a healthy weight too. Being overweight makes you more prone to conditions such as pre-eclampsia and high blood pressure.

Foods to avoid in pregnancy

There are certain foods you should while you're pregnant. Read about foods to avoid on the NHS website.

Early pregnancy symptoms (at 12 weeks)

Your signs of pregnancy may include:

  • an aching stomach
  • nausea
  • mood swings
  • a metallic taste in your mouth
  • sore breasts
  • indigestion and heartburn
  • headaches
  • dizziness
  • new likes and dislikes for food and drink
  • a heightened sense of smell
  • a white milky pregnancy discharge from your vagina
  • light spotting (see your doctor if you get bleeding in pregnancy)
  • cramping, a bit like period pains
  • darkened skin on your face or brown patches – this is known as chloasma or the "mask of pregnancy"
  • greasier, spotty skin
  • thicker and shinier hair
  • bloating and the feeling of being bloated (read ways to cope with bloating on week 10's page)

Read Tommy's guide to common pregnancy symptoms.

What does my baby look like?

Your baby, or foetus, is now 5.4cm long from head to bottom, which is about the size of a plum.

The internal organs and muscles have grown, and the heartbeat can be picked up on an ultrasound scan. The skeleton is made up from tissue and hardening into bone.

The sex organs have formed, although most scans will not be able to tell your baby's sex until later.

Composite. One side shows a foetus attached to a placenta by the umbilical cord. The foetus is now recognisable as a baby, with a proportionally large head. Other side shows an adult hand with a plum in its palm.
Your baby is about the size of a plum.

Action stations

As you start to feel more energetic, you could go and visit local maternity units and try and think about where you would like to have your baby. You can always change your mind later.

You may already have ideas about how you want to give birth – this is known as your birth plan. Try and stay flexible at this stage – we'll come back to birth plans in future weeks.

See your midwife or GP

Share the news with your GP or ask for an appointment with a midwife at your doctors' surgery. Alternatively you can refer yourself to your local hospital – look for contact details on their website.

You'll need to arrange a booking appointment. This usually takes place between weeks 8 and 12, and takes around an hour.

You can talk about the options for your pregnancy and the birth. Plus you'll be offered screening tests for infectious diseases, and conditions such as Down's syndrome. You could ask about the Maternity Transformation Programme and how it could benefit you.

You will be offered your first dating scan any time now.

If it's your first pregnancy, you will probably have around 10 appointments and 2 scans in total.

Consider telling your work

Many women will tell their employer after 12 weeks, once the risk of miscarriage reduces, and they've had their first scan.

Once you tell your employer, you have maternity rights and can attend antenatal appointments during paid work time.

You can also ask for a risk assessment of your work place to ensure that you're working in a safe environment.

Antenatal classes

Ask your midwife or doctor about online antenatal classes – they may be able to recommend one. The charity Tommy's has lots of useful information on antenatal classes and preparing you for birth.

Antenatal classes will give you the chance to meet other people and prepare you for parenthood. The NCT offers online antenatal classes with small groups of people that live locally to you.

Smoking, drinking and caffeine in pregnancy

Do your best to stop smoking and give up alcohol, and go easy on the tea, coffee and anything else with caffeine.

Ask your midwife or GP for support.

Vitamins in pregnancy

Take prenatal vitamins. You're advised to take 400 micrograms of folic acid, every day, until at least week 12. This helps your baby's nervous system to form and offers some protection from conditions such as spina bifida.

To keep bones and muscles healthy, we need vitamin D. From late March/early April to the end of September, most people make enough vitamin D from sunlight on their skin.

However, between October and early March, you should consider taking a daily vitamin D supplement because we cannot make enough from sunlight.

Some people should take a vitamin D supplement all year round, find out if this applies to you on the NHS website. You just need 10 micrograms (it's the same for grown-ups and kids).

Check if you're entitled to free vitamins.

Exercising in pregnancy

It's recommended that you do 150 minutes of exercise a week while pregnant.

You could start off with just 10 minutes of daily exercise – perhaps take a brisk walk outside. Check out Sport England's #StayInWorkOut online exercises (scroll to the pregnancy section).

Listen to your body and do what feels right for you.

Healthy eating

There's no need to eat for 2. You just need to eat a healthy balanced diet, with a variety of different foods every day, including plenty of fruit and veg. Have a look at our guide to healthy eating in pregnancy.

You may be able to get free milk, fruit and veg through the Healthy Start scheme.

Emotional and mental wellbeing

How are you today? If you're feeling anxious or low, then talk to your midwife or doctor. They can point you in the right direction to get all the support that you need. You could also discuss your worries with your partner, friends and family.

You may be worried about your relationship, or money, or having somewhere permanent to live.

Don't keep it to yourself. It's important that you ask for help if you need it.


Getting pregnant again might be the last thing on your mind. However, now is a good time to start planning what type of contraception you would like to use after your baby is born.

Getting pregnant again could happen sooner than you realise and too short a gap between babies is known to cause problems. Talk to your midwife or doctor to help you decide.

Sexually transmitted infections (STIs)

Do you think you or your partner could have an STI? If so, get checked out, as this could affect your baby's development. Talk to your midwife or GP, or visit a sexual health clinic.

Long-term conditions

If you have a long-term health condition, then let your specialist or GP know you're pregnant as soon as possible.

Don't stop taking any regular medication without discussing it with your doctor first.

Want to know when the baby's due?

Use the NHS's pregnancy due date calculator. You'll get a more accurate date from your doctor or midwife when you have a dating scan (usually at 8 to 14 weeks).

More in week-by-week

Week 13 – the 2nd trimester

Week 13 marks the start of the 2nd trimester, which means you're now a 3rd of the way through your pregnancy and hopefully through the worst of your symptoms.

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