Is there a relationship between heavy menstrual cycle and temporary vision loss?

Possibly: If you're experiencing extremely heavy bleeding (menorrhagia) then you may be anemic which can cause dizziness and temporary loss of peripheral vision. It's a good idea to see your ob/gyn and be check out for the source of bleeding, check your hematocrit to see if you're anemic and treat the cause. Good luck.

Low BP or Anemia: You may be experiencing orthostatic hypotension which can be exacerbated by anemia or dehydration. I recommend a full eye exam and routine blood work as a starting point.

Lens-Iris Diaphragm: If baseline anemia is present, retinal ischemia is possible but not likely. You may have changes in the lens-iris diaphragm and mild myopia from hormonal changes, which can be verified with an optometry visit. Suspect latent hyperopia and mild presbyopia. Rule out plateau iris configuration/syndrome with your ophthalmologist.