The role of extracellular matrix in normal and pathological pregnancy: Future applications of microphysiological systems in reproductive medicine

Remodeling of extracellular matrix in the womb facilitates the dramatic morphogenesis of maternal and placental tissues necessary to support fetal development. In addition to providing a scaffold to support tissue structure, extracellular matrix influences pregnancy outcomes by facilitating communication between cells and their microenvironment to regulate cellular adhesion, migration, and invasion. By reviewing the functions of extracellular matrix during key developmental milestones, including fertilization, embryo implantation, placental invasion, uterine growth, and labor, we illustrate the importance of extracellular matrix during healthy pregnancy and development. We also discuss how maladaptive matrix expression contributes to infertility and obstetric diseases such as implantation failure, preeclampsia, placenta accreta, and preterm birth. Recently, advances in engineering the biotic–abiotic interface have potentiated the development of microphysiological systems, known as organs-on-chips, to represent human physiological and pathophysiological conditions in vitro. These technologies may offer new opportunities to study human fertility and provide a more granular understanding of the role of adaptive and maladaptive remodeling of the extracellular matrix during pregnancy. Impact statement: Extracellular matrix in the womb regulates the initiation, progression, and completion of a healthy pregnancy. The composition and physical properties of extracellular matrix in the uterus and at the maternal–fetal interface are remodeled at each gestational stage, while maladaptive matrix remodeling results in obstetric disease. As in vitro models of uterine and placental tissues, including micro-and milli-scale versions of these organs on chips, are developed to overcome the inherent limitations of studying human development in vivo, we can isolate the influence of cellular and extracellular components in healthy and pathological pregnancies. By understanding and recreating key aspects of the extracellular microenvironment at the maternal–fetal interface, we can engineer microphysiological systems to improve assisted reproduction, obstetric disease treatment, and prenatal drug safety.