RESUMEN
To evaluate the role of factor XII deficiency in cases of habitual abortions. A case control study was conducted on 50 women with history of three or more consecutive first-trimester abortions [group A] of unexplained nature from outpatient clinic of Shatby Maternity University Hospital, and 25 healthy women with no history of recurrent miscarriage, thrombotic disease or adverse pregnancy outcomes [group B]. Blood sample was taken from each patient to assay the following parameters: protein S [PS], protein C [PC], antithrombin III [ATIII], and coagulation factor XII [FXII]. The subsequent miscarriage rate with abnormal FXII is significantly higher than that with normal FXII. However, there were no statistically significant differences in the subsequent miscarriage rates between normal and abnormal PC, PS and ATIII values. Factor XII deficiency might play a role in recurrent miscarriages