Every Week Counts…

The goal of a healthy pregnancy is to remain pregnant for at least 39 weeks

Why 39 weeks?

Remaining pregnant for the full term of 39 weeks is one of the best ways to give your baby the time needed to grow and develop.1
During the third trimester, the fetus continues to grow in size and weight. The lungs are still maturing and the fetus begins to position itself head-down. By the end of the third trimester, the fetus is about 19 to 21 inches long and weighs, on average, six to nine pounds. Fetal development during the third trimester includes:
  • The fetus can see and hear.
  • The brain continues to develop.
  • The kidneys and lungs continue to mature.
  • By the 36th week, the head may "engage" (drop into the pelvic area) - a process called "lightening."
  • The bones of the skull remain soft to make it easier to pass through the birth canal.
  • For many babies, the irises of the eyes are slate blue. The permanent eye color will not appear until several days or weeks after birth.
  • The fetus can suck its thumb and has the ability to cry.
  • By 39 weeks, the fetus' lanugo has disappeared almost completely.
  • By 39 weeks, the lungs have matured completely.
  • The baby is covered in vernix caseosa (or simply called vernix), a creamy, protective coating on the skin.
  • The head will usually turn downward during the last couple of weeks of pregnancy.
When is induction of labor necessary?
In some cases, labor has to be "induced," which is a process of stimulating labor to begin. The reasons for induction vary. Labor induction is not done before 39 weeks of pregnancy unless there is a problem. Some common reasons for induction include the following:
  • The mother and/or fetus are at risk
  • The pregnancy has continued too far past the due date
  • The mother has preeclampsia, eclampsia, or chronic high blood pressure
  • Diagnosis of poor growth of the fetus

Own your birth experience. Call 888-31-BIRTH or request an appointment with an OB/GYN or midwife to get started.

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Helpful Links
For more information, visit the March of Dimes website by clicking here.

Due Date Calculator
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