Purpose: DNA-damaging factors have been reported in patients that failed to achieve pregnancy after assisted reproductive technologies (ART). The hypothesis was that increased circulating cell-free DNA released by damaged cells could predict unfavorable conditions leading to failed ART treatment. The objective was to compare the relative concentrations of cell-free DNA in the luteal phase sera of nonpregnant versus pregnant patients.
Methods: Frozen-thawed sera (30 IVF cases) were obtained 1 week after embryo transfer. There were 16 pregnant and 14 nonpregnant cases and controls consisting of male sera (n = 8 cases). Modified isocratic capillary electrophoresis was performed and the images analyzed for cell-free DNA.
Results: Circulating cell-free DNA were identified in the sera of all patients. The serum concentrations of high (12 kb) and low (1 kb) molecular weight cell-free DNA were similar for both nonpregnant and pregnant patients. Male control sera had higher cell-free DNA concentrations compared with females. Evaluation of sera from a control case showed no fluctuations in cell-free DNA concentrations throughout specific days of the menstrual cycle.
Conclusions: The results do not support the use of the luteal phase cell-free DNA concentration as a marker for failed pregnancies. The equal concentrations of high and low molecular weight cell-free DNA and ladder band-like gel patterns suggested cell apoptosis as the source of DNA.