Abstract: An endometrial brush and method of using, the endometrial brush including a slidable protective sleeve for protecting bristles of the endometrial brush from wetting and contamination by cervical tissue during insertion of the endometrial brush through the cervix and into the endometrial cavity of the patient. The protective sleeve is composed of tubular flexible material which is slid forward along a shaft of the endometrial brush to cover the bristles during insertion. After the bristle section of the brush is in its desired position in the endometrial cavity, the protective sleeve is slid backward along the shaft, thereby uncovering the bristles. The handle is then manipulated to cause the bristles to scrape the walls of the endometrial cavity, thereby collecting sample tissue and/or cells. The brush is then withdrawn through the cervix. The collected sample is smeared on a microscope slide and analyzed.