Physics-based modeling of the pregnant woman

High quality obstetric images have become readily available with fast magnetic resonance imaging protocols or new 3D ultrasound probes. These obstetric images provide detailed information which can be used to create realistic models of the fetus at different stages of gestation. Unfortunately, the anatomy of the mother is only partially visible in the obstetric images and a full model of the pregnant woman can only be based on deformations of a non-pregnant woman body. Numerical pregnant women models are useful for a variety of applications, including dosimetry studies to assess the potential health effects of low-frequency electro-magnetic fields generated by power lines and electrical devices, planning of delivery procedure or training of obstetrical echographers. Only few models of pregnant women have been developed up to now, and they all lack realism and medical accuracy in representing the different stages of gestation and the anatomical variability of the fetal anatomy and positioning. This paper describes a novel methodology to create a set of detailed 3D pregnant women based on a series of controlled automatic deformations of a generic woman body envelope to insert pre-segmented utero-fetal units using a physics-based interactive modeler.