We've partnered with the American Institute of Ultrasound Medicine (AIUM), Johns Hopkins, and the March of Dimes to create this unique peak into Baby's development inside the womb. These images reveal all the intricate details of your baby's growth -- from a collection of cells to a full-term newborn. While most women may only receive one or two ultrasounds during pregnancy, which is normal, this slideshow of the 2nd trimester of pregnancy gives you a look at each week of development.
Week 16 (14 weeks from conception)
Fetal Size: Length, 4 1/3 to 4 2/3 inches, crown to rump; weight, 2 3/4 ounces.
Fetal Development Milestones: Baby's lower limbs are now well-developed. Toenails are forming and your baby's eyes and ears continue to move into the proper place. Facial muscles are beginning to work.
What You're Seeing: In this closeup view of Baby's profile, you can see how his facial features are becoming more defined. Notice that the sonographer has measured the length of his nasal bone. This specialized measurement may be useful in screening for some genetic abnormalities.