Everything you need to know about week 21 of pregnancy

21st Week of Pregnancy (Week 21)

Welcome to week 21 – you are now in the middle of your 6th month of pregnancy and moving towards the second half of this special time. Many expectant mothers experience the 21st week of pregnancy as a particularly pleasant phase: your bump is clearly visible, your baby is noticeably active, and physically you may feel better than at the beginning of your pregnancy.

Your baby is making daily progress in its development, especially in terms of movement, weight, and sensory perception. There are also many changes happening for you as a mum-to-be – your body continues to adapt to the new life growing inside you.

The 21st Week of Pregnancy at a Glance

Your baby in week 21:

• In the 21st week, your baby is about 26–27 cm long and weighs around 350–400 grams.
• It is busy training: grasping, swallowing, kicking – movements you can now feel regularly.
• The digestive system is working: your baby swallows amniotic fluid, which travels through its digestive tract.
• The skin is still thin, but protected by vernix caseosa.
• Sensory perception continues to develop – your baby reacts to voices, light, and gentle touches through the abdominal wall.
  
  

Your body in week 21:

• Your uterus continues to grow and now clearly extends above your navel.
• You can now feel your baby regularly – for many expectant mothers, a particularly special moment.
• Typical companions: calf cramps, heartburn, circulatory fluctuations or a pulling sensation in the groin.
• Your skin is also changing – stretch marks or increased pigmentation are not uncommon.
• Weight gain in week 21 of pregnancy is usually around 5–7 kg – but this varies individually.
  
  
  

Development of the Baby in Week 21

Your baby is growing strongly – both in size and in weight. In the 21st week of pregnancy, it is about 27 cm long and moves confidently through the amniotic fluid. Many babies now make their first attempts at coordinated movements, such as grasping with their hands or pushing off with their feet.

The sensory organs are now so well developed that your baby recognises your voice and can even perceive soothing music. The little heartbeat is also strong and regular. The nerve pathways in the brain continue to differentiate – an important step in responding to stimuli.

The immune system is strengthened by antibodies passed on from the mother, and more meconium (the baby’s first stool) is deposited in the intestine – a sign of active digestion. The tiny lips, eyelids, and eyebrows are taking on increasingly defined shapes – a true sign of just how human your baby already looks.

Your Body in the 21st Week of Pregnancy

By week 21, you are visibly “pregnant”. Your bump is growing, and your body weight is increasing – both are healthy signs of progress and can be tracked in your pregnancy calendar. Many women notice their baby’s movements particularly strongly at this stage, as there is still plenty of room for your baby to turn and stretch freely.

Typical symptoms such as heartburn, calf cramps, circulatory fluctuations, or increased sweating are completely normal at this time. Make sure to take regular breaks, wear comfortable clothing, and maintain a balanced diet with plenty of fluids.

This is a good time to start thinking about birth preparation – for example with pregnancy yoga, a birth preparation course, or by talking with your midwife. As the second trimester draws to a close, the topic of birth becomes more present – gently prepare yourself for this.