Diagnosed multi follicle given fostimon injection on cyclicday 11&12 with no oral medicine what is the chance of getting pregnant?

Depends on follicles: It depends on how many follicles you have. For most women doing Clomid (clomiphene) (oral med) only their chance is around 8-12% with an IUI. If your taking injections and have at least 3 eggs your chances are between 15-22% with an IUI. Obviously the more follicles (eggs) that are mature the better your chances of success. This also increases your multiple (twins,triplet) rate.