At 21 weeks, your baby is roughly the size of a carrot.
By the end of week 22, they are the size of a sweet potato.
Your baby’s eyebrows and eyelashes are very well formed by now. Your baby’s eyes even have functioning retinas, although they do keep their eyes closed still. Your baby’s sense of taste is also developing now, with taste buds quickly growing, and your baby can detect a few different flavors in the amniotic fluid they are practicing swallowing.
A small layer of fat is developing beneath your baby’s skin, which will help them start to practice regulating their own temperature. The vernix we’ve mentioned before (a cottage cheese-like substance) is still coating their skin, which helps to protect the skin from getting wrinkled or damaged from constantly being wet.
Your baby’s lungs are still continuing to progress. The alveoli (which are small air sacs in the lungs) are growing and expanding, but not nearly ready for breathing air yet.