21 weeks pregnant
At 21 weeks you are in month 5 and the second trimester. Your baby is about the size of a carrot: 27.1 cm and 398 g.
As big as
carrot
Length
27.1 cm
Weight
398 g
Month
5
Trimester
second trimester
To go
133 days
Averages. Measured crown to rump up to week 20, crown to heel after that. Healthy babies vary a lot.
Your baby this week
Swallowing and 'breathing' amniotic fluid: everything gets practised.
Your body
Your bump is visibly growing; clothes start to fit differently.
Good to know
Taste buds are developed; what you eat flavours the amniotic fluid.
To sort around these weeks
- Find out how maternity leave and pay work for you and your employer.
- Start thinking about antenatal classes and who will support you after the birth.
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Frequently asked questions
How many months is 21 weeks pregnant?
21 weeks pregnant falls in month 5 of your pregnancy.
Which trimester is 21 weeks?
At 21 weeks you are in the second trimester.
How big is a baby at 21 weeks?
On average 27.1 cm, about the size of a carrot. Healthy babies vary a lot.
How long to go at 21 weeks?
Until your due date (40 weeks): 19 weeks, 133 days.
All weeks
General information, not medical advice. If in doubt, call your midwife or GP. Sources: WHO fetal growth charts (Kiserud et al., PLoS Med 2017); Robinson and Fleming 1975; NHS, Your pregnancy and baby guide.