Evaluation of serum creatine kinase levels in ectopic pregnancy

Objective: To analyze whether increased serum creatine kinase (CK) levels are useful in early detection of ectopic pregnancy (EP). Design: Prospective cohort study. Setting: Patients in a university-based reproductive endocrinology and infertility practice. Patients: Infertile women who achieved clinical pregnancy. Interventions: Serum CK with isoenzymes levels were drawn after sonographic evaluation in patients achieving clinical pregnancy. Main Outcome Measures: Comparison of serum CK levels in patients with EP versus those with normal and abnormal intrauterine pregnancy (IUP), both separately and together as one group. Results: There was no significant difference in mean total CK levels for patients with EP (82.25 +/- 81.39 IU/L; conversion factor to SI unit, 1.00) versus normal IUP (62.54 +/- 44.79 IU/L), abnormal IUP (55.15 +/- 3.46 IU/L), or all IUP (60.87 +/- 40.72 IU/L). The mean gestational ages were similar in all three groups: EP, 46.78 +/- 6.65 days; normal IUP, 47.56 +/- 8.29 days; and abnormal IUP, 47.86 +/- 13.30 days. Conclusion: Serum CK levels do not help to predict EP for infertility patients achieving conception. To assist in preventing maternal morbidity, a more discriminative test is needed to identify this condition early in gestation.