Modeling of the biomechanical behavior and growth of the human uterus during pregnancy

Premature birth poses a challenge to public health, with one in ten babies being born prematurely worldwide. The pathological distension of the uterus can create tension in the uterine wall, triggering contractions that may lead to birth, including premature birth. While there has been an increase in the use of computational models to study pregnancy in recent years, ethical challenges have limited research on the mechanical properties of the uterus during gestation. This study proposes a biomechanical model based on a stretch-driven growth mechanism to describe uterine evolution during the second half of the gestational period. The constitutive model employed is anisotropic, reflecting the presence of fibers in uterine tissue, and it is also considered incompressible. The geometric model representing the uterine body was derived from truncated ellipsoids, subject to intrauterine pressure as loading. Simulation results indicate that the proposed model is effective in reproducing growth patterns documented in the literature, such as simultaneous increases in intrauterine volume and uterine tissue volume, accompanied by a reduction in uterine wall thickness within limits reported in experimental data.