Persistent Antiphospholipid Antibodies Appear Not to Jeopardize Pregnancy

Soh MC, Pasupathy D, Gray G, Nelson-Piercy C. Persistent antiphospholipid antibodies do not contribute to adverse pregnancy outcomes.Rheumatology (2013) Published online May 16.

Women with persistent antiphospholipid antibodies (aPLs) apparently have the same adverse pregnancy outcomes as those under treatment for antiphospholipid syndrome (APS) and even as unmatched controls, a five-year British study has shown.

The authors say theirs is the largest – and perhaps the first -- case-controlled study comparing women who have persistent aPLs with others who have obstetric APS.

The study included 73 women with persistent aPLs (measured more than 12 weeks apart on at least two separate occasions) and 73 women on aspirin therapy for obstetric APS, both groups delivering at a single institution, as well as 293 matched controls from low-risk clinics. Women who had concurrent systemic lupus erythematosus (SLE) were excluded from the trial.

The outcomes of interest included rates of pregnancy-induced hypertension (PIH), PIH with proteinuria, preterm delivery, and infants small for gestational age (SGA). These were similar for all three groups.

Most strikingly, the researchers note that rates of SGA -- a reflection of placental insufficiency characteristic of obstetric APS – were low among in women with aPL, and similar to controls. This was true even after adjustment for maternal age and medical comorbidities.

In the absence of other risk factors, the researchers conclude, the data suggest that pregnant women with aPL on aspirin do not need intense antenatal surveillance or special  modified management.