Labor & Delivery

Why the Last Weeks of Pregnancy Count

This article is for women thinking about scheduling their babyís birth.

More and more births are being scheduled a little early for non-medical reasons. Experts are learning that this can cause problems for both mom and baby. If possible, itís best to stay pregnant for at least 39 to 40 weeks.

There are lots of important things happening to your baby in the last few weeks of pregnancy. For example, your babyís brain and lungs are still growing. Thirty-nine weeks gives your baby all the time he needs to grow before heís born.

baby's brain at 35 weeks and 39 weeks

You might not have a choice about when to have your baby. If there are problems with your pregnancy or your babyís health, you may need to have your baby earlier. But if you have a choice and youíre planning to schedule your babyís birth, wait until at least 39 weeks.

If youíre planning to schedule your babyís birth, print out this article and take it with you to your next checkup. Ask your doctor or certified nurse-midwife (CNM) the questions below.

Why Babies Need Time
If your pregnancy is healthy and youíre planning to schedule your babyís birth, itís best to stay pregnant for at least 39 weeks. Babies born too early may have more health problems at birth and later in life than babies born full term. Being pregnant 39 weeks gives your babyís body all the time it needs to grow.

Hereís why your baby needs 39 weeks:

  • Important organs, like his brain, lungs and liver, get all the time they need to develop.
  • He is less likely to have vision and hearing problems after birth.
  • He has time to gain more weight in the womb. Babies born at a healthy weight have an easier time staying warm than babies born too small.
  • He can suck and swallow and stay awake long enough to eat after heís born. Babies born early sometimes canít do these things.

Why Scheduling an Early Birth Can Be a Problem
Experts are learning that scheduling an early birth for non-medical reasons can cause problems for mom and baby. For example:

  • Your due date may not be exactly right. Sometimes itís hard to know just when you got pregnant. If you schedule to induce labor and have a cesarean birth (also called a c-section) and your date is off by a week or two, your baby may be born too early.
  • Inducing labor may not work. If your labor is induced, the medicine your doctor or CNM gives you may not start your labor. When this happens, you may need to have a c-section.
  • A c-section can cause problems for your baby. Babies born by c-section may have more breathing and other medical problems than babies born by vaginal birth. (Most babies are born by vaginal birth. The motherís uterus contracts to help push the baby out through the vagina, also called the birth canal.)
  • C-sections can cause problems in future pregnancies. Once you have a c-section, you may be more likely in future pregnancies to have a c-section. The more c-sections you have, the more problems you and your baby may have, including problems with the placenta
  • A c-section is major surgery for mom. It takes longer for you to recover from a c-section than from a vaginal birth. You can expect to spend 2 to 4 days in the hospital after a c-section. Then youíll need 4 to 6 weeks after you go home to fully recover. You also could have complications from the surgery, like infections and bleeding. So itís important to stay in touch with your health care provider even after you go home.

The March of Dimes and obstetric provider groups advise that you wait until at least 39 weeks to induce labor or have a c-section if it is needed. Wait this long unless there are medical problems that make it necessary to have your baby earlier.

Questions to Ask Your Provider
These questions may be useful when you talk to your doctor or CNM about having your baby. Print out this article and take it with you to your next prenatal care checkup and ask these questions.

If you doctor or CNM recommends delivery before 39 weeks:

  • Is there a problem with my health or the health of my baby that may make me need to have my baby early?
  • Can I wait to have my baby until Iím closer to 39 weeks?

About inducing labor

  • Why do you need to induce labor?
  • How will you induce labor?
  • Will inducing labor increase the chance that Iíll need to have a c-section?

About c-section

  • Why do I need to have a c-section?
  • What problems can a c-section cause for me and my baby?
  • Will I need to have a c-section in future pregnancies?

August 2009

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