Overview

Antiphospholipid (AN-te-fos-fo-LIP-id) syndrome occurs when your immune system mistakenly creates antibodies that make your blood much more likely to clot.

This can cause dangerous blood clots in the legs, kidneys, lungs and brain. In pregnant women, antiphospholipid syndrome also can result in miscarriage and stillbirth.

There's no cure for antiphospholipid syndrome, but medications can reduce your risk of blood clots.