Your Baby Week 17:
Your baby now weighs more than the surrounding placenta. She measures about 4.4 to 4.8 inches (about 11 to 12cm) from crown to rump and weighs about 3.5 ounces (100g). She is positioned halfway between your pubic bone and your navel.
Fat, which is important for your baby's metabolism and heat production is beginning to form around this time.
The placenta, which will weigh more than a pound at full term, is also developing rapidly. It is now a large and well-established network of blood vessels responsible for exchanging nutrients and waste to support your baby.