Predictors of Pregnancy Outcome in Systemic Lupus Erythematosus (SLE) and Antiphospholipid Syndrome (APS)

Inclusion Criteria: * Patient pregnant with live intrauterine pregnancy, as defined by positive test for elevated β-HCG, but ≤ 12 weeks by gestation (for subjects without aPL antibodies) and ≤18 weeks (for subjects with aPL antibodies) * Patient between the ages of 18-45 and able to give informed consent, or age \< 18 years with parental consent * Hematocrit \> 26% * For APL positive: * aCL: IgG \>= 40 GPL units; IgM \>= 40 MPL units * Positive LAC (RVVT, Kaolin, dilute TTI or PTT LA) * Anti-β2GPI: IgG \>= 40 GPL units; IgM \>= 40 MPL units * For control subjects: * At least one successful pregnancy * No history of fetal death (death of conceptus ≥ 10 weeks' gestation) * No more than 1 miscarriage \< 10 weeks' gestation * No history of positive aPL in local lab or positive aPL in core labs at screening * Not currently a smoker * No medical problems requiring chronic treatment Exclusion Criteria: * Diabetes mellitus (Type I and Type II) antedating pregnancy * Known or suspected hereditary complement deficiency (defined by CH50 = 0)