Week 39: Your pregnancy
Your baby's growth: Skull bones
Even as late as the 39th week, there's one part of your baby's body that hasn't quite finished developing: the two soft spots on her head called the fontanels, where the skull bones haven't yet joined together. These areas allow the flexible skull bones to bend without damaging the brain as your baby travels down the birth canal.
Because of the strength of the contractions during labor, many newborn heads look elongated or cone-shaped right after birth. The bones will return to their round shape within a few days after birth. During your baby's first year, the skull will harden; by 18 months the soft spots will have completely hardened.
Other last-minute developments:
- Skeleton. It continues to develop. Your baby now has 300 bones (about 100 more than an adult does, since some bones fuse together as the child grows).
What's happening with you
- Weight gain. You're almost at the end of your pregnancy. Your pregnancy weight probably won't increase too much more from this point forward.
Contractions. Your body is preparing itself for labor, and you may begin experiencing Braxton Hicks contractions, which can be as strong as real contractions. But unlike real labor, these contractions are irregular and tend to stop and start. They help to trigger the pre-birth process of effacement and early dilation.
Although false contractions feel real, they aren't strong enough to make the cervix start thinning out or dilating. They may wax and wane for days or a few weeks before the onset of true labor. It can be hard to differentiate true and false labor, but contractions of true labor tend to get progressively stronger and more regular.
- Water break. Another sign of labor—the rupture of your amniotic sac (water breaking)—could happen at any moment. When water breaks, the sensation you may feel can range from a startling gush of water to a steady trickle. Some women never notice their water breaking at all.