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Pregnancy: Weeks 35-40

This article describes the development of your baby and your body during weeks thirty five through fourty of your pregnancy.

Pregnancy: Weeks 35-40

The last weeks of your pregnancy give your baby time to grow in length and weight.

A human fetus at 40 weeks. At this time your baby will weigh between 6 and 8 pounds and will measure about 18 to 22 inches in length.

Week Number 35

  • Babies born at Week 35 have a 99 percent chance of survival. The lungs are fully developed and the respiratory problems that used to kill these preemies are now easily treated.

Weeks Number 36 and 37

  • More fat layers are added to help control body temperature after birth.

Week Number 38

  • Your baby is now "full term." This means that if he's born today he'll be considered a full-grown baby. Babies born before 38 weeks are called premature babies.

Week Number 39

  • The baby sheds her fuzzy layer of lanugo hair and the vernix caseosa, which is the skin coating that covers a fetus to protect the skin. The baby swallows this waste and will discharge it as his first bowel movement in a blackish mixture called meconium.
  • All organs are ready to function outside your womb.
  • The lungs are the last organs to mature. They should be fully developed by this time.

Week Number 40

  • Bingo! This is the due-date week when your baby just might make her entrance. But then again, maybe she did that last week or will wait until next week. Remember that due dates are rarely exact. (Only 5 percent of babies are born on their due dates.) Even carrying a baby to Week 42 is considered normal. After that, the baby is post-term.
Baby Talk

A baby delivered after Week 42 is called post-term.

What a month! The anticipation can drive even the calmest expectant mom crazy. But you can take your mind off this pregnancy that seems never-ending by shopping for all those cute baby thing that your new baby will be using very soon!

Back to Weeks 31-34

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