I have studied this topic extensively for my PhD at the Department of Engineering, University of Cambridge. A copy in PDF format can be downloaded here: A Biomechanical model of Fetal Head Moulding (pdf 6 MB)
This work was also published in the Journal of Biomechanics, Fetal head moulding: finite element analysis of a fetal skull subjected to uterine pressures during the first stage of labour, (pdf 687 KB) of which you can download a reprint.
Snapshots of fetal head moulding are shown below, illustrating the change of shape of the fetal skull during the first stage of labour. Note that deformations are magnified with a factor 4. Fetal Head Moulding movie (wmv 21 KB): If you encounter problems opening the movie, save the file to your hard drive first and open with a media player.
| Front view of undeformed fetal skull|| Front view of deformed fetal skull|
| Lateral view of undeformed fetal skull|| Lateral view of deformed fetal skull|
| Top view of undeformed fetal skull|| Top view of deformed fetal skull|
A small project combining the methodologies to assess fetal head moulding and the augmented reality based surgical navigation resulted in this flawed but entertaining augmented reality forceps simulation (avi 5 MB).
The more scientifically justified (but less entertaining) part of this study, on the effect of the forceps on moulding can be found in a paper published in a satellite workshop of MICCAI 2004. Simulating obstetric delivery in an augmented environment (pdf 1 MB)
Snapshots of the change of shape of the fetal skull from applying obstetric forceps are shown below (left is undeformed; right is deformed). Note that deformations are magnified with a factor 4.
|Undeformed fetal skull||Deformed fetal skull after forceps application|
Author: Dr. Rudy Lapeer