How Pregnancy Works


Once her cervix is completely dilated, the mother is ready to start pushing. The combined force of her pushes and uterine contractions move the baby down the birth canal. Eventually the baby's head will make its way down to the mother's perineum (the tissue that stretches between the vagina and rectum). Pressure on the perineum can be intense, and feel like burning or stinging when the baby "crowns," or when the widest part of its head becomes visible.

A procedure called an episiotomy involves cutting the perineum to make more room for the baby and prevent the vagina from tearing. Although this procedure used to be routine, it's not done very often anymore. Sometimes the vagina tears by itself as the baby passes through.

When the baby's head finally emerges completely, the doctor or midwife will suction out its nose and mouth and check to make sure that the umbilical cord is not wrapped around its neck. With another push or two, the baby's body should be out. The doctor, nurse or midwife will dry the baby off with a towel, finish suctioning out its mouth, and clamp the umbilical cord. Sometimes doctors allow the mother's partner or another family member or friend to cut the cord.

Click on the play button to see the progression of vaginal delivery.

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Although the baby is out, labor is not quite over. The mother still needs to deliver the placenta, but it usually takes no more than one quick push. After the placenta is out, her uterus will continue to contract to seal off the blood vessels where the placenta was attached.

If the birth is not progressing well, or if either the mother or baby's health is in jeopardy, the doctor may perform a cesarean section, or c-section. An anesthesiologist numbs the mother from the waist down with an epidural or spinal anesthesia, and the doctor makes an incision in the mother's abdomen, just above the pubic bone. He opens the uterus, drains the amniotic fluid and removes the baby. Unless there are complications, the baby is treated in much the same way as he is following a vaginal delivery.

Typically after a few days in the hospital, the parents can bring home their new bundle of joy!

For more information on pregnancy and related topics, check out the links below.

Related HowStuffWorks Articles

More Great Links


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  • Episiotomy. BabyCenter.
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