I have been anemic my whole life. Been seeing a hematologist for 5 years. Why are you going to a obgyn ? You need a hematologist. Iron infusion work you just need them more often most likely some people need them monthly according to my hematologist. Yes Bariatric surgery causes anemia. You don’t need a colonoscopy you need a infusion. My numbers were similar to your before my surgery I get infusion 2 or 3 times per year so I am not worried