Can Vitamin B12 Deficiency, Cause Irregular Menses Flow?

Hi, may I answer your health queries right now ? Please type your query here...I have bleeding between periods for 8 months. All tests come back negative, infections etc. U/S normal. I'm 34 and had and they my gp doesn't feel necessary to repeat my smear test as last one within 18 months, should I insist. Although my gp did look at cervix whilst taking swabs and said looked fine. Also I have tested very b12 deficient level 100 which I'm now gettin treatment for, could this be causing my menstrual irregularities?