Serum anti-endometrial antibodies and first trimester pregnancy loss.

Serum anti-endometrial antibodies (AEA) have been studied as a marker for endometriosis and implantation failure. We sought to determine if the presence of AEA in the serum of pregnant patients is associated with first trimester pregnancy loss including complete abortion. This is a prospective pilot case control study of 30 patients presenting with first trimester pregnancy loss compared to a control group of 30 first trimester pregnant patients with a normal course for the presence of serum AEA. The control group was selected using propensity matching of patient characteristics. AEA assays were performed by a single operator blinded to clinical status of patients. The mean maternal age in the study and control groups was not statistically significant (26.1 +/- 5.7 vs. 24.2 +/- 4.5 years, p < 0.155). A history of pregnancy loss was not significantly greater in the study group (12/30 = 40.0%) as compared to the control group (8/30 = 26.7%, p < 0.412). In both study and control groups, 40% of the samples tested positive for AEA; therefore, we found no evidence of an association between the presence of AEA and pregnancy loss. These findings in our pilot study suggest that presence of serum AEA does not appear to be a marker for early pregnancy loss.