Calculation of membrane tension in selected sections of the pelvic floor.

Introduction And Hypothesis: A mathematical model to estimate membrane tensions (Mt) at the urogenital hiatus and midpelvis in patients with and without prolapse is proposed. For that purpose the complex structures of the pelvic floor were simplified and, based on assumptions concerning geometry and loading conditions, Laplace's law was used to calculate Mt. The pelvic cavity is represented by an ellipsoid in which the midpelvic and hiatal sections are described by an ellipse.

Neonatal and maternal outcomes in twin gestations > or =32 weeks according to the planned mode of delivery.

Objective: To determine a possible relationship between neonatal and maternal outcomes in twin gestations and the planned mode of delivery.

Study Design: A single-centre retrospective cohort study in twins > or =32 weeks of gestational age was performed. Baseline characteristics, and neonatal and maternal outcomes were documented according to the planned mode of delivery: a planned caesarean section or a planned vaginal birth.