A Focused Look at Obesity and the Preimplantation Trophoblast

Obesity is associated with a myriad of adverse reproductive outcomes including miscarriage, fetal growth abnormalities, and preeclampsia. While the mechanisms involved are likely multifactorial, the potential impact of obesity on the preimplantation embryonic trophoblast cannot be overlooked - particularly given the role the trophoblast plays in endometrial invasion and implantation. Appropriate trophoblast function is critical in establishing a normal pregnancy. Insufficient or impaired trophoblast invasion is associated with early miscarriage, fetal growth abnormalities, and preeclampsia. Thus, any negative impact obesity may impose on the trophoblast may represent a root cause for several adverse reproductive outcomes seen more commonly among obese women. While little is known about obesity's specific impact on the human trophoblast, in vitro studies and animal models provide insight. In this article, we review what is known on this topic and provide a basis for future work, investigating therapeutic targets for improved reproductive outcomes in the setting of maternal obesity.