What do systematic reviews say?

Heparin plus aspirin vs aspirin

Heparin plus aspirin showed no clear difference in adverse events in the mother ‐ Bleeding compared with aspirin (low certainty).

• Aspirin or heparin or both for improving pregnancy outcomes in women with persistent antiphospholipid antibodies and… 2020 · Cochrane Headline outcomes only
  RR 1.65 [0.19, 14.03]
  1 study · 31 participants
  Low