Without being able to see the actual slide - it can only be said for sure that sickle cell blood cells are deformed - it is visually apparent when viewed through a microscope - the deformity deters the blood cell from the cells intended optimal capacity to hold molecules (such as hemoglobin) and it makes it harder for the blood cell to travel efficiently through the body's arteries and veins.
This answer depends on whether you are taking about the menstrual cycle or the ovarian cycle