Rodents, Sheep, and Nonhuman Primates as Models for Human Pregnancy and Fetal Development

This chapter describes animal models of reproductive disorders, fetal development, and pregnancy-related disorders. Novel technologies include genome editing by the CRISPR-Cas9 system, posttranslational gene silencing, single-cell transcriptomics, and in vitro cultivation of blastocysts. In the mouse, they are suitable for the study of early embryonic development and to identify genes of potential significance for pregnancy disorders. The chronically instrumented sheep model continues to provide important data about fetal physiology and may be more relevant than rodents for modeling disorders in the last trimester of human pregnancy. Nonhuman primates are increasingly useful because of advances in whole-genome sequencing, surgical techniques, and RNA-silencing technologies, as well as developments in the microbiome field. These advances further the value of nonhuman primate models for resolving urgent public health issues, such as Zika virus infection, in pioneering treatment of infertility, and for understanding the pathophysiology of preeclampsia. Because of current interest in developmental models of adult disease, we separately discuss the contribution of these animal models to research on fetal growth restriction. Finally, we discuss some alternative animal models and attempt to predict future trends in the exploration of pregnancy-related disorders.