Endometrial aneurysm
An endometrial venous aneurysm can rupture and bleed into the uterus causing blood to pass out of the urogenital opening and cause anaemia in the rabbit. Venous aneurysm’s form along a weakened part of the vein wall, these can then rupture causing bleeding, endometrial venous aneurysms are considered a congenital defect in unneutered female rabbits.
One of the signs of an endometrial aneurysm is blood in the urine
©Derek Knottenbelt