Pregnancy-associated changes in uterine-luteal relationships in cows: A mini-review

The main function of the bovine corpus luteum (CL) is the production of progesterone. Adequate luteal progesterone is crucial for determining the physiological duration of the estrous cycle and for achieving a successful pregnancy. The CL is regulated not only by hypophyseal gonadotropin, but also by a number of intraluteal substances including steroids, peptides and prostaglandins. Although regulation of luteal function throughout the estrous cycle has been intensively studied, studies of the CL during the entire gestation period are limited. Understanding the role of luteal function during pregnancy might lead to ways to improve reproductive efficiencies and reduce the number of defective fetuses. Therefore, the purpose of this review is to summarize our current understanding of the gene expression profiles of bovine CL throughout the gestation period and to focus on recent studies documenting the interactions between the CL, uterus and conceptus in cows.