Number and sequence of preceding miscarriages and maternal age for the prediction of antiphospholipid syndrome in women with recurrent miscarriage

Objective To investigate the relationship between the number and sequence of preceding miscarriages and antiphospholipid syndrome (APS). Design Retrospective cohort study. Setting Recurrent miscarriage (RM) clinic. Patient(s) Women who attended the RM clinic from 1988 to 2006. Intervention(s) None. Main Outcome Measure(s) Number, type, and sequence of previous pregnancies were compared between women with APS and women with unexplained RM. Result(s) A total of 1,719 patients were included; 312 (18%) had APS, and 1,407 (82%) had unexplained RM. The mean maternal age (32.6 years) did not differ between women with and without APS. The median number of miscarriages was three in both groups. A total of 865 women (50%) had a history of at least one live birth, with no difference between the two groups. In both groups, 97% of the women had a history of consecutive miscarriages. Conclusion(s) The number of preceding miscarriage, type and sequence of previous pregnancies, and maternal age were not associated with APS in women with RM. There is no increased diagnostic yield for APS after three miscarriages rather than after two miscarriages and no increased diagnostic yield for APS after consecutive miscarriages rather than after nonconsecutive miscarriages. Therefore, APS testing should be considered for all women with two or more miscarriages.