Week 20 of pregnancy
Week 20 sits in the middle stretch of pregnancy, the second trimester.
What's developing
The skin is covered in a white, greasy layer called vernix, thought to protect it. The baby kicks, turns and may suck their thumb. [1]
What you might notice
Cramp can wake you at night with sharp pain in your calves. Rub the muscle hard or pull your toes up toward your ankle. [1]
Everyone's pregnancy is different. If something worries you, call your midwife or doctor.
A tip for this week
Ask about the whooping cough vaccine. It's usually offered around week 20 and can be given from week 16 to week 32. [1]
Questions you could bring to your next appointment
- When is my mid-pregnancy scan?
- Will I be offered a glucose test?
- Is there anything I should change about exercise or work?
Questions
When will I feel the baby move?
The NHS says between 16 and 24 weeks. In a first pregnancy you might not feel movements until after 20 weeks.
What if I haven't felt the baby move by 24 weeks?
Tell your midwife or doctor. They'll check your baby's heartbeat and movements.
Is my baby exactly this size?
Probably not exactly. The length is the average the NHS gives for this week, and the weight is the middle value (50th percentile) of the WHO fetal growth charts. Your scan results are the ones that count.
Sources
- NHS: 20 weeks pregnant guide Checked October 30, 2026
- NHS: Your baby's movements Checked October 30, 2026
- WHO: The World Health Organization fetal growth charts (Kiserud et al., PLoS Medicine 2017), table 11: estimated fetal weight Checked October 30, 2026
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