Week 17
Your Baby's Development
At about 5.1 inches (13 cm) from crown to rump and weighing 4.9 ounces (140 grams), your baby is still very tiny.
The placenta, which nourishes the fetus with nutrients and oxygen
and removes wastes, is growing to accommodate your baby. It now contains thousands
of blood vessels that bring nutrients and oxygen from your body to your baby's developing
body.
Your Body
You may notice that your breasts have changed considerably since your
pregnancy began. Hormones are preparing your breasts for milk production — more
blood is flowing to the breasts, and the glands that produce milk are growing in preparation
for breastfeeding. This can increase your breast size (many women increase one to
two cup sizes) and make veins become visible. Buy supportive bras in a few different
sizes to manage your breast growth during pregnancy.