Your baby at 20 weeks
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.
You at 20 weeks
At 20 weeks pregnant, you're halfway through your pregnancy. 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.
Find out how to deal with common pregnancy problems including feeling faint, feeling hot, cramp, constipation and more.
Things to think about
- what happens at the 20-week scan, and what it's looking for
- what to expect if your antenatal screening finds something
- your feelings, worries and relationships
You usually have the whooping cough vaccine at around 20 weeks pregnant.
If you are 20 weeks pregnant and have not been offered the whooping cough vaccine, contact your midwife or GP surgery.
To give your baby the best protection against whooping cough, you should have the vaccine before 32 weeks of pregnancy.
Pregnancy can be a trigger for domestic abuse or domestic violence, and existing abuse may get worse. Abuse can be physical, sexual, emotional or psychological, and it puts you and your baby in danger.
If you're pregnant and being abused by your partner or a family member, you can speak to your midwife or doctor, or call the 24-hour freephone National Domestic Abuse Helpline, run by Refuge, on 0808 2000 247.
Start4Life has more about you and your baby at 20 weeks of pregnancy
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Video: Where does my pregnancy weight come from?
In this video, a midwife discusses where the extra weight in pregnancy comes from.
Media review due: 14 March 2026