Pregnancy week 21

Your baby’s development

At 21 weeks your baby is about the size of a carrot. This week's theme is the digestive system: your baby swallows amniotic fluid, and the intestines learn to absorb the water and small amounts of sugar in it. Leftovers collect in the bowel as a dark, sticky substance called meconium, which will become the first stool after birth. Bone marrow starts to take over blood cell production, so the baby no longer depends only on the liver and spleen. Eyebrows and eyelids are well defined by now. Your baby is active, kicking, turning, and sometimes reacting when you eat or when there is a sound. Because a sleep pattern is forming, there may be busy and quiet times of day. Measurements are averages. Development moves at its own pace in every pregnancy; your doctor interprets ultrasound measurements, and small differences are usually ordinary.

Changes in the mother

As your belly grows, you may notice tightness, itching or stretch marks on the skin. Moisturiser can ease itching. Constipation and haemorrhoids are common now; drinking plenty of water, eating fibre and walking regularly help. Slight swelling around the ankles may show at the end of the day; raising your legs and avoiding long periods of standing bring relief. If swelling is also marked in the morning, or increases suddenly in the face or hands, let your doctor know. Your baby's movements may be clearer now; some days are quieter and some busier, which is natural. If your sleep is disturbed, take short rests during the day. Resting when you feel tired is a natural part of this journey.

To do this week

• If the detailed ultrasound has not been done yet, ask your doctor about the date.
• Take short daily breaks with your legs raised.
• Choose comfortable, supportive shoes for pregnancy.
• Start looking into antenatal classes and birth preparation courses.

Tip for the partner

Consider attending a birth preparation class together; learning about the process side by side builds confidence.

Nutrition tip

Drinking plenty of water and eating more fruit and vegetables helps against constipation.