Pregnancy Week By Week

21 Weeks Pregnant: Development, Symptoms and Care

At 21 weeks pregnant, your pregnancy may feel more visible and more physical. You might be following up scan results, finding comfortable clothes or learning what your baby’s movements feel like. A useful focus this week is making sure your own questions are being answered, not keeping up with a checklist.

Your baby’s development at 21 weeks

Your baby continues to grow during this part of the second trimester. Fine hair called lanugo and the protective coating known as vernix cover the skin. Growth and organ development continue over the coming weeks; looking more like a newborn does not mean being ready for birth.

Body changes and symptoms

You may notice stretch marks or darker areas of skin during pregnancy. These do not arrive on a fixed schedule. New itching needs medical advice, even if there is no rash; it should not automatically be put down to stretching skin.

Heartburn and constipation can make an otherwise ordinary day uncomfortable. Smaller meals and staying upright after eating may help reflux. For constipation, fluids, fibre and activity you can manage may help. Ask your pharmacist or clinician about treatments suitable for pregnancy if symptoms persist.

Getting to know movements

Most people feel the first movements between 16 and 24 weeks. They can begin as flutters or small rolls. Your experience may be different from a friend’s or from an earlier pregnancy.

There is no set number you have to count. If movement decreases or changes in a way that concerns you, call your midwife, doctor or maternity unit immediately. Do not wait until the next day. If you have never felt movement by 24 weeks, contact your care team; you can ask sooner whenever you are worried.

Following up the anatomy scan

If you have chosen a morphology scan but it has not been arranged, contact your care team promptly. It is usually offered around 18 to 22 weeks. They can advise on appropriate timing and available appointments.

If you have already had the scan, check that someone has explained the report and any follow-up. A scan does not identify every condition, and a chromosome screening blood test does not replace assessment of anatomy. Ask what a finding means for your pregnancy before making assumptions from a report or an online search. Our prenatal tests guide explains the different purposes of tests.

Making the next few weeks manageable

Ask at your next visit about whooping cough vaccination, ideally given between 20 and 32 weeks of each pregnancy in Australia, and the blood glucose test usually offered between 24 and 28 weeks. Timing may be tailored to your circumstances.

Keep a short list of symptoms, appointments and questions in one place. If work, transport, money or caring responsibilities make appointments difficult, tell the service so you can discuss practical options. Pregnancy care needs to fit a real life, not just a calendar.

When to seek medical help

In Australia, call 000 for heavy bleeding, severe abdominal pain, severe breathing difficulty, chest pain or collapse. Do not drive yourself if faint or very unwell.

Contact your GP, midwife or hospital immediately for vaginal bleeding, leaking fluid, fever, vomiting that prevents drinking, persistent or worsening pain, or concerning contractions. Severe headache, blurred vision, sudden swelling or pain under your ribs also needs urgent assessment. If your usual team is unavailable, seek urgent care rather than waiting for an appointment.