During placental development and carcinogenesis, cell invasion and migration are critical events in establishing a self-supporting vascular supply. Interleukin (IL)-11 is a pleiotropic cytokine that affects the invasive and migratory capabilities of trophoblast cells that form the placenta during pregnancy, as well as various malignant cell types. The endometrium is the site of embryo implantation during pregnancy; conversely, endometrial carcinoma is the most common gynaecological malignancy. Here, we review what is known about the role of IL-11 in trophoblast function and in gynaecological malignancies, focusing primarily on the context of the uterine environment.