Early-onset preeclampsia - The impact of antiphospholipid antibodies on disease severity

Antiphospholipid antibodies have been associated with various obstetric complications, including recurrent pregnancy loss, preeclampsia, intrauterine growth restriction, placental insufficiency, and late fetal loss. Despite the amassed body of evidence emphasizing the association between antiphospholipid antibodies and preeclampsia, the severity of preeclampsia with regard to antiphospholipid antibodies status has not been elucidated. This study aimed to evaluate whether early-onset preeclampsia with severe features before 34 weeks' gestation is clinically different when associated with antiphospholipid antibodies.

In this retrospective case-control study, we collected data on pregnancy outcomes of 101 women with singleton pregnancies who delivered prior to 34 weeks of gestation due to preeclampsia with severe features. The antiphospholipid antibodies status of 55 of these women was available for analysis. The study group comprised 20 women with positive antiphospholipid antibodies (positive-aPL group), while the control group comprised 35 women without antiphospholipid antibodies (negative-aPL group). Obstetric and neonatal outcomes, laboratory results and pregnancy complications were extracted from medical records.

In the clinical setting of early-onset preeclampsia with severe features necessitating delivery before 34 weeks gestation, positive-aPL women were hospitalized earlier (29, IQR 26.3-32, vs. 32, IQR 28-33 weeks gestation, P = 0.05), gave birth at a significantly earlier gestational age (30, IQR 28.3-32.8 vs. 33, IQR 30-34, P = 0.02) with a lower mean birth-weight (1266.7 ± 579.6 vs. 1567.3 ± 539.7 g, P = 0.058) compared with negative-aPL women. Furthermore, platelet nadir was significantly lower for positive-aPL compared with negative-aPL women (97 ± 49×10³/µL vs. 141 ± 61×10³/µL, P < 0.001) and maximal serum creatinine was higher (1.0 ± 0.3 mg/dL vs. 0.9 ± 0.1 mg/dL, P = 0.03). Rates of neonatal complications were low and comparable between groups, except for higher rates of retinopathy of prematurity requiring treatment in the study group (30.0% vs. 5.7%, p = 0.02), and there was a trend for higher perinatal mortality among study group infants.

The presence of antiphospholipid antibodies in women with early-onset preeclampsia with severe features is associated with earlier, more severe disease course. Expedited screening for antiphospholipid antibodies in cases of early-onset severe preeclampsia may be considered, along with close monitoring for pregnant women with positive antibodies.