In the last weeks of pregnancy, a fetus usually moves so his or her head is positioned to come out of the vagina first during birth. This is called a vertex presentation. A breech presentation occurs when the fetus’s buttocks, feet, or both are in place to come out first during birth. This happens in 3–4% of full-term births.
Occasionally fetuses with certain birth defects will not turn into the head-down position before birth. However, most fetuses in a breech presentation are otherwise normal.
Your health care professional may be able to tell which way your fetus is facing by placing his or her hands at certain points on your abdomen. By feeling where the fetus's head, back, and buttocks are, it may be possible to find out what part of the fetus is presenting first. An ultrasound exam or pelvic exam may be used to confirm it.
External cephalic version (ECV) is an attempt to turn the fetus so that he or she is head down. ECV can improve your chance of having a vaginal birth. If the fetus is breech and your pregnancy is greater than 36 weeks your health care professional may suggest ECV.
ECV can be considered if you have had a previous cesarean delivery.
The health care professional performs ECV by placing his or her hands on your abdomen. Firm pressure is applied to the abdomen so that the fetus rolls into a head-down position. Two people may be needed to perform ECV. Ultrasound also may be used to help guide the turning. The fetus's heart rate is checked with fetal monitoring before and after ECV. If any problems arise with you or the fetus, ECV will be stopped right away. ECV usually is done near a delivery room. If a problem occurs, a cesarean delivery can be performed quickly, if necessary.
More than one half of attempts at ECV succeed. However, some fetuses who are successfully turned with ECV move back into a breech presentation. If this happens, ECV may be tried again. ECV tends to be harder to do as the time for birth gets closer. As the fetus grows bigger, there is less room for him or her to move.
Most fetuses that are breech are born by planned cesarean delivery. A planned vaginal birth of a single breech fetus may be considered in some situations. Both vaginal birth and cesarean birth carry certain risks when a fetus is breech. However, the risk of complications is higher with a planned vaginal delivery than with a planned cesarean delivery.
In a breech presentation, the body comes out first, leaving the baby’s head to be delivered last. The baby’s body may not stretch the cervix enough to allow room for the baby’s head to come out easily. There is a risk that the baby’s head or shoulders may become wedged against the bones of the mother’s pelvis. Another problem that can happen during a vaginal breech birth is a prolapsed umbilical cord. It can slip into the vagina before the baby is delivered. If there is pressure put on the cord or it becomes pinched, it can decrease the flow of blood and oxygen through the cord to the baby.
With each cesarean delivery, these risks increase.
If you are thinking about having a vaginal birth and your fetus is breech, your health care professional will review the risks and benefits of vaginal birth and cesarean birth in detail. You usually need to meet certain guidelines specific to your hospital. The experience of your health care professional in delivering breech babies vaginally also is an important factor.
Amniotic Fluid: Fluid in the sac that holds the fetus. Anesthesia: Relief of pain by loss of sensation. Breech Presentation: A position in which the feet or buttocks of the fetus would appear first during birth. Cervix: The lower, narrow end of the uterus at the top of the vagina. Cesarean Delivery: Delivery of a fetus from the uterus through an incision made in the woman’s abdomen. External Cephalic Version (ECV): A technique, performed late in pregnancy, in which the doctor attempts to manually move a breech baby into the head-down position. Fetus: The stage of human development beyond 8 completed weeks after fertilization. Fibroids: Growths that form in the muscle of the uterus. Fibroids usually are noncancerous. Oxygen: An element that we breathe in to sustain life. Pelvic Exam: A physical examination of a woman’s pelvic organs. Placenta: Tissue that provides nourishment to and takes waste away from the fetus. Placenta Previa: A condition in which the placenta covers the opening of the uterus. Placental Abruption: A condition in which the placenta has begun to separate from the uterus before the fetus is born. Prelabor Rupture of Membranes: Rupture of the amniotic membranes that happens before labor begins. Also called premature rupture of membranes (PROM). Preterm: Less than 37 weeks of pregnancy. Ultrasound Exam: A test in which sound waves are used to examine inner parts of the body. During pregnancy, ultrasound can be used to check the fetus. Umbilical Cord: A cord-like structure containing blood vessels. It connects the fetus to the placenta. Uterus: A muscular organ in the female pelvis. During pregnancy, this organ holds and nourishes the fetus. Vagina: A tube-like structure surrounded by muscles. The vagina leads from the uterus to the outside of the body. Vertex Presentation: A presentation of the fetus where the head is positioned down.
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