Weekly Guide to Pregnancy: Week 21

Week 21
Week 21 

Your Baby

How big is my baby?

Fetal size: 18 cm (7.2 inches). Fetal weight 300 grams (10.5 ounces).

Your baby has been growing rapidly, but over the last week and during this week, growth slows down and your baby continues to develop and mature in other ways while continuing to gain weight. At 21 weeks, your baby can swallow amniotic fluid. Your baby absorbs the water from the fluid, while any other matter is pushed through to the bowel by the muscle movements of the small intestine. The first bowel movement your baby passes will contain the undigested matter from the swallowed amniotic fluid. This green-black or brown matter (called meconium) will be passed during, or soon after birth.

Your Pregnancy

What pregnancy symptoms will I be experiencing?

Normal weight gain up to and including week 21 is between 3.6 and 6.3 kg (8-14 pounds). The outward signs are there and people will really notice that you are pregnant.

You should really notice your baby's movements by now.

You may begin to see stretch marks on your abdomen and breasts, and you may also notice tiny red marks on your face or arms. Stretch marks should fade after birth and the red lines should disappear altogether. Another pregnancy symptom you may experience is leg swelling, especially if you have been on your feet for most of the day. Try to rest and put your legs up at some point during the day.

Now is the time to review your exercise program. Your size will affect your balance and mobility, so you should think about avoiding team contact sports such as netball, basketball, softball and volleyball. Try swimming, walking and yoga instead.

Heartburn and constipation are common complaints during pregnancy, and you may experience shortness of breath. You may also notice that your gums become spongier.

Learn more about your pregnancy


Read more information on Pregnancy and Birth on Essential Baby.

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