CD40LG and autoimmune polyendocrinopathy: The role of IgM aβ2GPItesting in the diagnosis of APS remains unclear and it considered to have little clinicalutility for thrombotic APS.38 In our cohort >50% of women with obstetric APS had low-titre IgM aCL and/oraβ2GPI (alone or in association with IgG antibodies).