At 21 weeks pregnant, white blood cells are under production. Leukocytes (or white blood cells) form our body's defense system. They help fight infections and diseases.
Your little one's skin has changed from translucent to become more opaque.
Your infant's tongue is fully formed. If you were able to peek you might catch your son or daughter practicing giving you a raspberry!
If your baby is a girl, her womb and vagina are formed. Unlike males, females have a limited supply of eggs in their lifetime. At this point your daughter will have 6 million eggs. This amount decreases to approximately one million by birth.
Baby swallows more in week 21 of your pregnancy. After your baby takes in amniotic fluid, his body absorbs the water in the liquid and moves the rest into the large bowel. This is good practice for his digestive system!
Wake and sleep periods become more consistent. Some research suggests that baby sets her internal clock to match the outside world's even before birth! Your eating and sleeping habits as well levels of light and noise serve as her signals.
Length is now measured crown to heel.
After 21 weeks of pregnancy, your baby measures about 10.51 inches (26.7cm) and weighs nearly 12.7 ounces (360g).