Table 1.

Sapporo criteria for APS classification.

Clinical and Laboratory Criteria
Vascular thrombosis	≥1 clinical episode of arterial, venous, or small vessel thrombosis. Thrombosis must be objectively confirmed. For histopathological confirmation, thrombosis must be present without inflammation of the vessel wall.
Pregnancy morbidity	≥1 unexplained death of a morphologically normal fetus ≥10 weeks of gestation. ≥1 premature delivery of a morphologically normal fetus <34 weeks of gestation because of. Severe preeclampsia or eclampsia defined according to standard definition. Recognized features of placental insufficiency. ≥3 unexplained consecutive miscarriages < 10 weeks of gestation, with maternal and paternal factors (anatomic, hormonal, or chromosomal abnormalities) excluded.
Laboratory criteria	Presence of aPL, on two or more occasions at least 12 weeks apart and no more than 5 years prior to clinical manifestations, as demonstrated by ≥1 of the following. LA. Medium to high-titer (>40 GPL or MPL, or >99th percentile) aCL IgG or IgM. Anti-β2 glycoprotein-I (anti-β2GPI) IgG or IgM > 99th percentile.