Comparison of histocompatibility between couples with idiopathic recurrent spontaneous abortion and normal multipara.

Since the immunological interaction between a mother and her intrauterine embryo is thought to be very important and since the human leukocyte antigens (HLA) are considered to be the most important correlative immunoresponsive antigens presently known, the present study was designed to investigate the HLA phenotype frequencies and antigen sharing percentages in couples suffering from recurrent abortion, as compared with normal fertile couples. The results showed that there were no HLA associations among these groups. The sharing study analyzed the similarities between single antigen groups (A, B, C, and DR) and multiple antigen complexes (AB and ABDR). The incidences for sharing more than one single antigen were 63.9%, 44.4%, 61.1% and 30.6% in the study group and 57.1%, 22.9%, 71.4% and 40.0% in the control group. Sharing of more than two antigens in the multiple antigen combinations were 36.2%, 47.2% for the study group and 22.9%, 42.9% for the control group. The statistical analyses reveals no significant differences. We conclude that although immunological reaction during the periimplantation period may be important and may play a role in later pregnancy stages, no single HLA antigen presentation or sharing of a certain number of antigens is related to the prognosis of pregnancy outcome.