Your baby takes on a more human form as his neck lengthens and his head is seen as separate from his body. The head is still about half the total length of your baby. The length of your baby can be measured on an ultrasound by measuring the distance between your baby's head (crown) and his bottom (rump). This is noted as the CRL (crown-rump length) measurement. The head is also measured: this is the biparietal diameter (BPD), which is the distance between the two parietal bones on each side of the baby's head.
Now that the neck is more developed and all the limb joints have formed, your baby can begin to make several movements. The completed diaphragm allows for breathing movements. In the gut, your baby's duodenum now opens up along its length, the small bowel starts to rotate and prepares to re-enter the abdominal cavity.
Within your baby's mouth, the hard palate has formed; the relatively large tongue makes it easier for your baby to move amniotic fluid through the nostrils rather than through his mouth with each breath.