Anti-annexin V antibodies in patients with early pregnancy loss or implantation failures

Objective: To describe the prevalence of annexin V antibodies (aANX) in wom en with early recurrent pregnancy losses (RPLs) or recurrent IVF-ET failure . Design: Retrospective data analysis. Setting: Tokai University Hospital, Kanagawa, Japan. Patient(s): Two hundred thirty-eight patients with RPLs, 48 patients with r ecurrent IVF-ET failure and 179 nonpregnant and 120 pregnant control group women. Intervention(s): None. Main Outcome Measure(s): ELISA was used to measure autoantibodies to annexi n V. Result(s): An ELISA system developed for aANX revealed a dose-dependent rel ationship between annexin V and aANX. The positive/negative cutoff was set at 7 multiples of the median based on the 99th percentile of normal nonpreg nant control group patients. Patients with RPLs (5.5%) or recurrent IVF-ET failure (8.3%) had a significantly increased incidence of aANX (IgG) compar ed with normal nonpregnant (1.1%) or pregnant control group women (0), wher eas the prevalence of aANX between both patient groups or between both cont rol groups was not statistically different. Specificity was confirmed by ab sorption studies using annexin V and by immunoblots. Conclusion(s): Our data show that aANX are associated with both RPLs and IV F-ET failure. We propose that anti-annexin V antibodies should be considere d a risk factor for these reproductive failures. (Fertil Steril(R) 2001;76: 694-9. (C) 2001 by American Society for Reproductive Medicine.).