As listed in Table 4, there were also no differences regarding the occurrences of mild, moderate or severe abdominal pain (P = 0.433), back pain (P = 0.752), shoulder pain (P = 0.955), nausea (P = 0.259), emesis (P = 0.593), allergy (P = 0.593) or colporrhagia (P = 0.371) within 2 h post operation between EPO group and ioversol group. The gene discussed is EPO; the disease is Allergy.