Approximately 4% of babies will enter the last month of pregnancy in the breech presentation. When the baby is in the breech position, the obstetrician may attempt to turn it to the head down position. This turning is known as version.
The idea behind version is quite simple. The obstetrician attempts to manipulate the baby to shift into a more favorable position. Usually that means encouraging the baby to perform a forward somersault, changing direction 180 degrees. If the version succeeds, the head will become the presenting part, and vaginal delivery will be much more likely and safer.
Unfortunately, version is not appropriate in all situations and is not without risks. It is appropriate only in a single pregnancy where the position of the baby can be accurately diagnosed (usually by ultrasound). It is not appropriate for multiple pregnancies. The baby should not be unusually large and the presenting part should not be deep in the pelvis. Also, there must be a normal amount of amniotic fluid. All these conditions ensure that the baby has room to turn and will not be injured by the manipulations of the obstetrician's hands. In addition, a non-stress test must be reactive (indicating fetal well-being), and there should be no signs of placental problems (for example, low fluid, growth retardation, or vaginal bleeding). Version may represent a stress to the baby, and if there is evidence that the baby is not receiving adequate oxygen and nutrients at rest, it should not be attempted.
Version must be performed at the hospital because of the small but significant chance of causing fetal distress by turning the baby. If the baby experiences slowing of the heart rate after turning (bradycardia), perhaps because of the umbilical cord tangling, emergency C-section delivery will be required.
The actual procedure is quite simple. The mother reclines on a firm table. An ultrasound, to confirm fetal position, and a non-stress test, to demonstrate fetal well-being, are done. Some obstetricians will administer a dose of terbutaline by injection before the procedure to prevent uterine contractions. The mother's abdomen is dusted with powder to allow the obstetrician's hands to slide across it easily. The obstetrician uses one hand to pull the presenting part up out of the pelvis. With the first hand cupping the presenting part, the obstetrician's other hand is placed at the back of the baby's head. Both hands are used to induce the baby to do a forward somersault. If the attempt succeeds, gentle pressure is exerted to push the head into the pelvis. The fetal heart rate should be monitored again to make sure that the new position does not cause fetal distress.
Version is successful approximately half the time. Not every baby will turn, and some babies who turn easily will turn back to their original position shortly after the procedure is completed. Nonetheless, if your obstetrician is comfortable and experienced with the procedure and there are no problems indicated, version is often worth trying. If successful, version reduces the risk to the baby from breech vaginal delivery, and the risk to the mother from C-section delivery.