Q. What is external version? How is it done, and does it really turn breech babies?
A. The procedure for “turning” a baby positioned in a breech presentation is called version.
At full term, almost all babies are positioned head down in the birth canal. Those babies are positioned in what is called the vertex, or cephalic presentation. About three percent of all pregnancies end with the head up, and either the feet or buttocks entering the birth canal first. This is what is commonly referred to as breech presentation.
At the present time in the United States, most pregnancies where the baby presents as a breech are delivered by elective scheduled cesarean section, if this is the first birth. The reasons given for the choice of cesarean delivery instead of vaginal delivery are that it provides a safer route of delivery, since in a breech delivery the head, usually the widest part of the baby, is delivered last. In the hands of an experienced obstetrician, with knowledge of approximate fetal size and with estimation of approximate pelvic size, vaginal delivery of a breech presentation can be safely attempted.
An alternative approach to cesarean section for breech presentation involves an attempt at turning the baby externally, with the intention of positioning the head in a downward position. This procedure, called external cephalic version, is usually performed approximately at the 37th week of pregnancy. It is usually not performed earlier than this since there is a likelihood of the smaller baby reverting to the breech position again. Also, by the 37th week of pregnancy, many breech babies will accomplish a rotation of the head into the birth canal on their own, without any assistance.
An external cephalic version, in the hands of a competent obstetrician can be a safe and successful alternative to automatic cesarean delivery. However, there are several things that must be done to insure the safety of the procedure. First off, fetal monitoring before and during the attempt is crucial. Remember that the baby is attached to the placenta by the umbilical cord, and turning the baby can pull on the cord.
Ultrasound (sonography) must be used to monitor the progress of the procedure and to assess the size of the fetus, the amount of fluid surrounding the baby, and the position of the placenta. The procedure should be done either in, or very near the labor and delivery area, since immediate delivery in the event of a problem might rarely become necessary.
The procedure itself involves using pressure applied to the mother’s abdomen to push the baby into the correct position. Recent studies have shown a low rate of problems associated with this procedure, but success rates show great variety.
This procedure should be discussed in detail with your obstetrician. It should not be attempted if either you, or your obstetrician is hesitant about the potential risks of the procedure itself. As with all medical procedures, the potential risk must be balanced by the benefits.