Using Magnetic Resonance Imaging (MRI), scientists have captured 3D images that show how infants' brains and skulls change shape as they move through the birth canal just before delivery.

‘Infants experience greater skull stresses during birth than previously thought, potentially underlying the asymptomatic brain and retinal bleeding seen in many newborns after vaginal delivery.’

In the new study, Ami and colleagues used 3D MRI to capture detailed images of seven infants' skulls and brains before and during the second stage of labor. The analysis revealed fetal head molding during the second stage of labor in all seven infants, with different parts of the skull overlapping to varying degrees among the infants. After birth, five of the newborns' skull and brain shapes returned to their pre-birth state, but the changes persisted in two of the infants. Two of the three infants with the greatest degree of fetal head molding were delivered by emergency C-section, but the third was delivered vaginally with minimal expulsive efforts. 




The authors note that a larger study is needed to confirm their findings, but that their work demonstrates the value of 3D MRI in capturing fetal head molding.
Ami adds: "During vaginal delivery, the fetal brain shape undergoes deformation to varying degrees depending on the degree of overlap of the skull bones. Fetal skull molding is no more visible in most newborns after birth. Some skulls accept the deformation (compliance) and allow an easy delivery, while others do not deform easily (non-compliance)."
Source-Eurekalert