Not necessarily. A receptive endometrium is one that has a thickness between 8-12 mm and a trilaminar aspect. An endometrial thickness greater than 13 mm is associated with a low implantation rate.
In addition, for an endometrium to be receptive it must have undergone several structural changes that can only be visualised after a biopsy and observation of the endometrial tissue under the microscope: presence of pinopods, endometrial glands, greater number of cells, etc.
Suggested for you: Uterine Receptivity As a Cause of Sterility.