Pregnancy calendar

weeks pregnant

21 weeks pregnant - what's happening

Wow - you're halfway there! Your baby is growing hair and starting to look much more like the baby you’ll meet at the end of your pregnancy.

21 weeks infographic.

What does my baby look like?

Your baby weighs in at around 350g and is about as long as a carrot. Although your baby’s ears began to form early on, they’ll start to be able to hear around now. They’ll be able to make out sounds from outside, including your voice and the voices of people around you.

Talk and sing to your bump if you feel like it, and encourage other family members to do the same - it can be a nice way to let others get involved.

It sounds a little strange but your baby has been growing a fine hair called lanugo all over their tiny body over the last few weeks. You’ll be relieved to hear it usually disappears before they're born (so they probably won’t come out furry!).

The hair on their head and eyebrows is starting to become a little thicker at the roots and showing signs of pigment. Do you think they’ll be blonde or dark?

See how your baby will develop over the coming weeks with BabyCentre's animated inside pregnancy video: weeks 21-27.

Your symptoms - what's happening

Sore head?

Mild headaches are common in pregnancy, often caused by hormones or dehydration.

However, if you’re more than 20 weeks pregnant, have a bad headache that lasts for more than two or three hours and paracetamol doesn’t help, it could mean you have high blood pressure. This can be a sign of pre-eclampsia.

Find out what to do if you have a severe headache that will not go away.

Are you suffering from cramps, swollen feet, indigestion or heartburn?

Here’s our guide to 10 common pregnancy complaints (and how to avoid them).

Actions to take

Concerned about your scan results?

If you’ve discovered that there’s a health complication with your baby, you’re probably feeling very anxious and shocked.

You can find lots of advice and information on the Antenatal Results and Choices website. They also have a helpline: 0800 077 2290.

Find out more about screening and diagnostic tests in pregnancy.

Can I start doing yoga if I’ve never done it before?

Yes - yoga is a great exercise to do during pregnancy as it doesn’t put too much strain on your joints.

Yoga has been shown to reduce anxiety and to help women stay calm in pregnancy and labour.

What can I eat to boost my iron levels now I'm pregnant?

Foods containing iron include red meat, oily fish, eggs, pulses (peas, beans and lentils, for example), wholegrain or wholemeal breads, nuts, green leafy vegetables, dried fruit and some breakfast cereals (look for ones with added iron).

Eating or drinking foods with vitamin C will help your body absorb the iron. Avoid tea and coffee, because this can have the opposite effect.

Enjoy bonding with your baby

You're halfway to meeting your baby! Stroke your tummy, talk to your baby and enjoy your pregnancy as much as you can.

Read more about supplements to take during pregnancy.


1. You and your baby at 21–24 weeks pregnant, NHS Choices: [accessed 5 May 2015] (last reviewed: 11 February 2015; next review due: 11 February 2017).

2. Lennart Nilsson (2009) A Child is Born, Jonathan Cape, p.207

3. Graven SN, Browne JV (2008) Auditory development in the fetus and infant, Newborn and Infant Nursing Reviews 8(4): 187–193:[accessed 12 March 2015].

4. Arabin B (2002) Music during pregnancy, Ultrasound in Obstetrics and Gynecology 20(5): 425–30: [accessed 12 March 2015].

5.;jsessionid=8356994E9CF8683BEBFA426268A1E65D.f01t03 p638

6. Ibid, p203

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Last reviewed on April 1st, 2015. Next review date April 1st, 2018.

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  • By Angel (not verified) on 19 May 2018 - 16:50

    Hi I was seeing my period all along notice my Tommy was getting so I did a pregnancy test it was positive went to the hospital they sound my belly got a heart beat measured my belly an exanine me den told me I am 21 weeks pregnant how is dat possible...? I had no symptoms nothing

  • By Midwife @Tommys on 21 May 2018 - 16:11

    Hi, It is possible to continue to have bleeds during a pregnancy and this may not be easily distinguished from a normal period. We hope you are pleased about the pregnancy and make good use of our website as you will need to catch up with all the information! Take care

  • By Filory jan (not verified) on 14 May 2018 - 13:31

    What i do.?

  • By Midwife @Tommys on 15 May 2018 - 09:53

    Hi Filory Jan
    Any abdominal pain, at any gestation of pregnancy needs to be reviewed as soon as possible at your local maternity unit triage by a midwife and Dr. In most cases, it's just for peace of mind. But abdominal pain isn't always normal and so worth getting checked out. Don't forget to take your pregnancy notes with you too.
    All the best
    Sophie,Tommy's Midwife

  • By Kortni (not verified) on 12 May 2018 - 11:13

    I was having abdomen pain on my right side went to the ER and found out it was from a fibriod that moved it was located outside on top of my uterus prior to this pregnancy and last year's miscarriage...
    now its on the left side it was causing alot of pain to walk also trying to sit up and get out of bed they prescribed me indocin for the pain temporary says it won't affect the baby now but it still possibly can later on I have taken Tylenol to help mask the pain but I was wondering because I am allergic to pcn is that medicine safe?
    I have only taken the one dose at the hospital which added stomach pain to what I was already feeling 2days later I seen a fibriod specialist he advised me its okay to take the medicine prescribed...since then I still refused and went back 2work so a coworker said try kosher pickle juice and it helped relieve alot of the pain and in a day or two it has faded alot nothing else helped during the 5days I was in pain not rest or stretching so is it possible that really worked or the fibriod pain just faded on it's own? is there anything else besides that will help me avoid the pain from coming back as I progress right now I am only 20 weeks???

  • By Midwife @Tommys on 14 May 2018 - 11:26

    Hi Kortni,
    Sorry to hear you have pain. As midwives, we can't advise about prescription medication as this is outside of our remit. Have you spoken to your pharmacist? Paracetamol is the preferred option for pain in pregnancy. If this isn't effective for you please speak to your GP.

  • By Abigail Naylor (not verified) on 7 May 2018 - 10:58

    Hi I’m 21 weeks 6 days today. I have felt my baby move the past week apart from since yesterday morning I’ve felt nothing. I gave birth to my son at 21 weeks in October so I’m worried about this baby now. I just want to thank you for any response that I may recieve.

  • By Midwife @Tommys on 10 May 2018 - 12:47

    Hi Abigail
    If you are ever concerned about fetal movement, and babies normal movements are somehow different - eg less frequent or a type of movement that worries you, then you need to attend your local maternity units pregnancy triage/day assessment unit asap if you have not already done so. They will check you and baby over there - don't forget to take your pregnancy notes with you!
    All the best
    Sophie,Tommy's Midwife

  • By Aziola (not verified) on 30 Mar 2018 - 06:51

    Am drinking one cup of coffee per day,dose it affect for my baby inside

  • By Midwife @Tommys on 3 Apr 2018 - 16:38

    Hi Ayziola
    One cup of coffee per day is fine. Here is our calculator below to help add up what else may contain caffeine during your day that you eat or drink...
    Sophie,Tommy's Midwife

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