Anatomy Introduction and gametogenesis. 3809eb3e Conceptus reaches uterine cavity at which stage? A 1 cell B 2 cell C 16 cell D 32 cell High-Yield Explanation Conceptus enters uterine cavity on the 4th day in Advanced morula (>32) cell stage. Note: In IVF Transvaginal inseion into uterus is done at 8 cell stage.