Among those, there were 16 cases (nine cases in group A and seven cases in group B) owing to poor ovarian response (no follicles of diameter ≥10 mm after administration of FSH for 7 days), and there were 6 cases (two cases in group A and four cases in group B) because of OHSS [with abdominal distention, nausea, vomiting, ascites, hydrothorax, hematocrit (HCT) >41%, pericardial effusion, white blood cell (WBC) >10000/mm3, oliguria or anuria, etc.]. This evidence concerns the gene BRD2 and ovarian hyperstimulation syndrome.