Caput Succedaneum and Molding: Ultrasound and Digital Correlations

Caput succedaneum is defined as a diffuse swelling of the fetal scalp caused by the pressure of the scalp against the dilating cervix during labor. Caput is often associated with molding and may extend across the midline (as opposed to cephalohematoma, which does not cross the suture lines). Prolonged pressure to the fetal scalp causes serosanguinous fluid to leak from the subcutaneous tissue into the area above the periosteum between the scalp and the lining of the periosteum with resultant edema and/or bruising. This location results in a collection of fluid that crosses over the cranial sutures (Fig. 21.1) [1, 2].