Sonographic assessment of fetal spine and head position during the first and second stages of labor for the diagnosis of persistent occiput posterior position: a pilot study

The results of this study suggest that the position of the head and spine during the second stage of labor could be useful indicators for predicting the OP position at delivery. The results also suggest that the OP position at delivery results from a failure of rotation from the OP position, rather than a malrotation from the anterior position. Studies with larger sample sizes are needed to confirm these results.