20 Weeks Pregnant: Pregnancy Symptoms & Baby Development

At 20 weeks pregnant your baby will be roughly 16cm from head to bottom (the size of a banana), and will weigh around 300g¹. Their heartbeat is strong enough to be detected easily. 

Your baby is now covered in a layer of white, creamy ‘vernix’, a substance that’s thought to protect their delicate skin². Later on, the slipperiness of vernix will help your baby make its way down the birth canal.

If you’re having a baby girl, her uterus will be developing¹, and her ovaries will already have seven million primitive eggs in them³. When she’s born, she’ll be carrying two million eggs³. If you’re having a baby boy, then this is the week when the testes start lowering from his abdomen³.

The development of your baby’s nerve cells is slowing, but more complex connections are forming - so much so that your baby can enjoy a satisfying stretch⁴.

Between weeks 18-20 of your pregnancy, you’ll be scheduled for an anomaly scan to ensure your baby is developing properly, and discuss next steps if there are any suspected issues. It’s no reason to worry.

Your placenta continues delivering nutrients to, and removing waste from, your baby, but your baby will soon become larger than your placenta. Your placenta continues growing, too, trebling in size by birth³. Because of its important role, the sonographer will also examine your placenta during your scan.

You may also start experiencing Braxton-Hicks contractions, or ‘false labour pains’⁵. Even as early as week 20 your body starts preparations for birth. The contractions are unpredictable, and not everyone will experience them. They can be caused by being too active, having a full bladder, or, conversely, dehydration. (See? Unpredictable.) The contractions are normally mild (you may not even notice some), vary in intensity and duration, and aren’t usually a cause for concern.

Iron is a key nutrient throughout pregnancy, and an important part of a balanced diet. The recommended daily intake for every woman, whether pregnant or not, is 14.8mg each day⁹. Your blood cells need iron to carry oxygen around your body¹⁰ and to your baby. Iron also contributes to your baby’s normal cognitive function¹¹.

Many women have lower haemoglobin levels during pregnancy, but iron supplements are only prescribed if they’re very low¹².

• Lean meat (always ensure it’s well cooked) 
• Oily fish, such as sardines
• Dark green veg, including broccoli, watercress, spinach and kale
  
• Cashew nuts
  
• Pulses, chickpeas, beans and lentils
  
• Whole grains, including wholemeal bread, and iron-fortified breakfast cereals
  
• Dried fruits, such as apricots, prunes and raisins
  
• Eggs

Moderate exercise is good for both you and your baby as long as you’re both healthy. Even if you’ve not exercised before, you can still start now, but go gently and choose low-impact exercises.

Walking

This is a perfect exercise for pregnancy, and walking at a quick pace is good for your heart. You should aim for three to five walks of 30 minutes each week¹⁵.

Yoga

This can help stretch and strengthen muscles, reduce pregnancy pains (especially lower back pain) and lower your blood pressure. Don’t try complex poses, especially twists, and avoid ‘Bikram hot yoga’¹⁵.

Swimming

This is great exercise that lets you build strength and aerobic stamina at the same time. You can swim three to five times a week, up to 30 minutes at a time¹⁵.