A method, apparatus, and kit for marking the opening between the fallopian tube and the uterus (tubal ostia) are provided. A marking dye provided in a marking assembly including a fluid dispenser coupled to a catheter having an open end and a guide wire. The catheter is inserted into the uterus and to a position adjacent the tubal ostia. When properly inserted, the fluid dispenser is activated to cause fluid to flow through the catheter and to the wall of the uterus to provide a mark. Once the mark is provided, endometrial ablation process can be provided in the uterus. The marks can then be used to guide the insertion of tubal occlusion devices.