Genes regulating implantation and fetal development: A focus on mouse knockout models

Timely and efficient regulation of blastocyst implantation and fetal growth are essential for the successful reproduction of viviparous mammals. Disruptions in this regulation can result in a wide variety of human gestational complications including infertility, spontaneous abortion, fetal growth restriction, and premature delivery. The role of several groups of factors, including cytokines, hormones, transcription factors, extracellular proteinases, and angiogenic factors has been suggested in both implantation and regulation of fetal growth. Due to the inherent difficulties of studying implantation and fetal development in humans, much of our knowledge of the genes involved in these processes has been derived from animal models. The critical genetic loci involved in blastocyst implantation and fetal growth will be discussed with a focus on those genes with available mouse knockout models.