Week by week pregnancy guide: 21 weeks pregnant

Everything you need to know...

21 weeks pregnant

You're now 21 weeks pregnant but what should you expect? Read week 21 of our week by week pregnancy guide to find out everything you need to know...

Tracking your pregnancy week by week is helpful for keeping on top of everything and getting prepared for your little one. Here's everything you need to know about being 21 weeks pregnant.

At 21 weeks pregnant you can start thinking about when you'd like to take your maternity leave and you might even want to start thinking about baby names. We've put together everything you need to know about this week of your pregnancy, so you can relax, knowing everything you're going through is normal...

Symptoms at 21 weeks pregnant

You may start to feel a bit breathless around this time as your uterus presses against your diaphragm and leaves less room for your lungs. If you're having trouble sleeping, try putting a pillow between your legs and get used to sleeping on your side.

Have a warm milky drink and snack before bed (hunger is a common cause for insomnia in pregnancy) and try to relax. Listen to soothing music, or a relaxation tape. But don't take sleeping pills, even herbal ones aren't advisable in pregnancy.

Up to 30% of mums-to-be suffer from leg cramps during pregnancy. These can be excruciatingly painful and often strike at night. If you're one of the unlucky ones, try sticking a pillow under your feet at night or even raising the foot of the bed. Another tip is to do some calf stretches several times during the day and before going to bed.

If you suffer from eczema you may find that it improves during pregnancy. This may be due to an increase in the body's natural steroid-like hormones that are produced during pregnancy.

Fetal development at 21 weeks pregnant

They are now around 26.7cm and weighs 360 grams. Their heart is getting stronger, legs are in proportion to the body and baby's putting fat on their bones. Because their muscular and nervous systems are now mature enough for them to stretch and move their limbs they'll become increasingly active... even doing backflips while there's room!

21 weeks pregnant

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The changes you should make at 21 weeks pregnant

Now's the time to start thinking about when you might want to go on your maternity leave. Usually, the earliest leave can start is 11 weeks before your expected week of childbirth, although many women prefer to work as close to their due date as possible so that they can have longer at home with their new baby.

Ask your GP or midwife for your maternity certificate called a MAT B1. This is proof that you're pregnant and confirms when your baby is likely to arrive. You must give it to your employer at least three weeks before you intend to take your maternity leave. Some women will have a foetal anomaly scan or amniocentesis this week, so that's another thing to consider.

Stephanie Lowe
Family Editor

Stephanie Lowe is Family Editor at GoodToKnow covering all things parenting, pregnancy and more. She has over 13 years' experience as a digital journalist with a wealth of knowledge and experience when it comes to all things family and lifestyle. Stephanie lives in Kent with her husband and son, Ted. Just keeping on top of school emails/fund raisers/non-uniform days/packed lunches is her second full time job.