Table 1: Criteria of obstetrical APS [3]. APS is diagnosed when at least one of the following clinical criteria and one of the following laboratory criteria are met.

Clinical criteriaBiological criteria

(i) 3 or more consecutive spontaneous abortions before the 10th WG*, with maternal anatomic or hormonal abnormalities and paternal and maternal chromosomal causes excluded(i) Lupus anticoagulant (LA) present in plasma, on two or more occasions at least 12 weeks apart, detected according to the guidelines of the International Society on Thrombosis and Haemostasis
(ii) One or more unexplained deaths of a morphologically normal fetus at or beyond the 10th WG*, with normal fetal morphology documented by ultrasound or by direct examination of the fetus(ii) Anticardiolipin (aCL) antibody of IgG and/or IgM isotype in serum or plasma, present in medium or high titer, on two or more occasions, at least 12 weeks apart, measured by standardized ELISA
(iii) One or more premature births of a morphologically normal neonate before the 34th week of gestation because of eclampsia or severe preeclampsia or recognized features of placental insufficiency**(iii) Anti 2glycoprotein-1 antibody of IgG and/or IgM isotype in serum or plasma (in titer >99th percentile), present on two or more occasions, at least 12 weeks apart, measured by standardized ELISA

WG: week of gestation.
**Placental insufficiency features include abnormal or nonreassuring fetal surveillance test, abnormal Doppler flow velocimetry waveform analysis suggestive of fetal hypoxemia, oligohydramnios, and postnatal birth weight less than the 10th percentile for the gestational age.