The length of the human umbilical cord in vertex and breech presentations.

The present study is based on two previously stated theories: (1) that the umbilical cord length is influenced by fetal motor activity and (2) that the breech presentation is associated with low fetal motor activity. From this one would expect the mean cord length to be shorter in breech presentations as compared with vertex. This was indeed found to be the case. An already known difference between the sexes regarding cord length was also confirmed, and a difference in male:female ratio in the two presentations is shown. The results of the study thus seem to support the two stated theories.