Blood spots are the result of broken capillaries in the reproductive system. When the capillary ruptures, a drop of blood leaks out and becomes part of the egg. The presence of a blood spot does not mean the egg is fertile or that an embryo is beginning to form. Egg processors attempt to identify and remove all eggs containing blood spots before eggs go into the carton. Occasionally one is missed, but if the blood spot is small, it can be removed and the egg used. For large blood spots the egg should be discarded.