Your baby's development
By the time you're 17 weeks pregnant, your baby is growing quickly and now weighs around 150g.
The face begins to look much more human, and eyebrows and eyelashes are beginning to grow. Your baby's eyes can move now, although the eyelids are still shut, and the mouth can open and close.
The lines on the skin of the fingers are now formed, so the baby already has his or her own individual fingerprints. Fingernails and toenails are growing, and the baby has a firm hand grip.
The baby moves around quite a bit, and may respond to loud noises from the outside world, such as music. You may not feel these movements yet, especially if this is your first pregnancy. If you do, they'll probably feel like a soft fluttering or rolling sensation.
Your baby is putting on a bit of weight, but still doesn't have much fat, so if you could see your baby now, she or he would look a bit wrinkled. The baby will continue to put on weight for the rest of the pregnancy and will "fill out" by the last few weeks before birth.
By 20 weeks, your baby's skin is covered in a white, greasy substance called vernix. It's thought this helps protect the skin during the many weeks in the amniotic fluid.
Your body halfway through pregnancy
At 20 weeks pregnant, you're halfway through your pregnancy. You might feel your baby move for the first time when you're around 17 or 18 weeks pregnant. Most first-time mums notice the first movements when they're between 18 and 20 weeks pregnant.
At first, you feel a fluttering or bubbling, or a very slight shifting movement. Later on you can't mistake the movements, and can even see the baby kicking about. Often, you can guess which bump is a hand or a foot.
You may develop a dark line down the middle of your tummy. This is normal skin pigmentation, as your tummy expands to accommodate your growing bump. Normal hair loss slows down, so your hair may look thicker and shinier.
Common minor problems can include tiredness and lack of sleep. Sleeplessness is common, but there's plenty you can do to help yourself sleep, including using pillows to support your growing bump.
Some women also get headaches. Headaches in pregnancy are common, but they could be a sign of something serious if they're severe.
Pregnancy scan
You'll be offered an anomaly scan when you're 18-20 weeks pregnant – this is to check for abnormalities in the baby. Your doctor or midwife can give you information about this and answer any questions.
Read more about screening for foetal abnormality.
Tips for mid-pregnancy
Exercise and keeping active in pregnancy is good for you and your baby. Find out what's safe and when you should take care.
Eating a healthy diet in pregnancy will help your baby to develop and grow, and help keep you fit and well.
You'll be offered ultrasound scans in pregnancy, including the anomaly scan between 18 weeks and 21 weeks and 6 days.
Warning signs to look out for
Bleeding from the vagina may be a sign of serious problems, so seek help for vaginal bleeding in pregnancy.
Itching in pregnancy can be a sign of the rare liver disorder intrahepatic cholestasis of pregnancy, sometimes called obstetric cholestasis or OC.
If you lose your baby, it's very important that you have all the support you need. Support is available from your care team and other organisations.
Find out more about miscarriage, ectopic pregnancy, and stillbirth.
You can save a to-do list online to keep track of all the essentials for your pregnancy.
Pregnancy week by week
Find out what's happening to you and your baby at:
0-8 weeks pregnant
9, 10, 11, 12 weeks pregnant
13, 14, 15, 16 weeks pregnant
21, 22, 23, 24 weeks pregnant
25, 26, 27, 28 weeks pregnant
29, 30, 31, 32 weeks pregnant
33, 34, 35, 36 weeks pregnant
37, 38, 39, 40 weeks pregnant
Over 40 weeks pregnant
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