Your baby now looks like a tiny newborn, and is around 20cm long. Twenty-two weeks is the earliest age at which premature babies have survived, although some of the essential body systems such as the brain still have a long way to develop.
Between weeks 18 and 22 you may be offered an anomaly scan, a detailed ultrasound in which the baby is checked for any major problems such as poor development of the central nervous system (brain and spinal cord). This scan can also detect multiples (twins or more) if your doctor or midwife hasn't already made this discovery.
From around week 20, mums often start to experience slight swelling (oedema) or puffiness, because pregnancy causes the body to retain more fluid. It's usually most obvious around the feet, ankles, and hands. Make yourself more comfortable by wearing clothes that are looser around your wrists and ankles, and roomier shoes. Avoid standing for long periods and rest with your feet up. Let your doctor know if you experience very sudden swelling in your hands and face, which can be a sign of pre-eclampsia.