Babies born in the breech position (bottom first) are at increased risk of complications at birth because of a delay in the birth of the head. Turning a breech baby to head first in late pregnancy may reduce these complications. A procedure called external cephalic version (ECV) describes when practitioners use their hands on the woman's abdomen to gently try to turn the baby from the breech position to head first. There are a number of treatments that may help the success of the ECV. These include using tocolytic drugs (drugs like betastimulants, calcium channel blockers that relax the womb), stimulating the baby with sound through the mother’s abdomen (acoustic stimulation), increasing the fluid surrounding the baby (transabdominal amnioinfusion), pain relieving drugs injected into the mother’s lower back to produce regional analgesia (epidural or spinal analgesia) or giving the mother opioid drugs to help her to relax.
The review of trials found 25 randomised controlled studies involving 2548 women. Most studies (17 studies, involving 1876 women) looked at the tocolytic drugs. The results showed that babies are more likely to turn head first during ECV, and to remain head first for the start of labour, if women receive tocolytic drugs (in particular betastimulants). These drugs also reduced the number of caesarean sections but there were not enough data collected on possible adverse effects. In addition, there is too little evidence to show whether the other ways of trying to help ECV were effective. Further research would be helpful.