Gynaecology & Obstetrics The consequences of Rh incompatibility are not serious during first pregnancy because: A In first pregnancy only IgM antibody is formed B Antibody titer is very low during primary immune response C IgG generated is ineffective against fetal red cells D Massive hemolysis is compensated by increased eryth ropoiesis 💡 Explanation The consequences of Rh incompatibility are not serious during first pregnancy because: ✓ Correct Answer: A. In first pregnancy only IgM antibody is formed