Antiphospholipid syndrome is an autoimmune condition in which antibodies make the blood more likely to clot. It can cause clots in veins or arteries and complications in pregnancy.
It may occur alone or alongside lupus. Having the antibodies without any clot or pregnancy problem is not the syndrome, and many such people never need strong blood thinners.
Symptoms
- Deep vein thrombosis, with a swollen painful calf
- Pulmonary embolism, with sudden breathlessness or chest pain
- Stroke or transient ischaemic attack at a young age
- Recurrent early miscarriage or a late pregnancy loss
- Severe pre-eclampsia or poor fetal growth
- A lace-like purple skin pattern (livedo reticularis)
- A low platelet count on blood tests
Causes and risk factors
The immune system produces antibodies against proteins bound to phospholipids on cell surfaces, chiefly beta-2 glycoprotein I. These activate the lining of blood vessels, platelets and the placenta. Why the antibodies appear is unknown. They can show up briefly after infections, which is why a single positive test means little. Risk of clotting rises with smoking, oestrogen-containing contraception, surgery, immobility and pregnancy.
How it is diagnosed
- Lupus anticoagulant: A clotting-based test. It is unreliable while you are taking most anticoagulants, so timing matters.
- Anticardiolipin and anti-beta-2 glycoprotein I antibodies: Measured as IgG and IgM. Moderate or high levels count.
- Repeat testing at 12 weeks: The diagnosis requires persistent positivity at least 12 weeks apart plus a clinical event.
- Imaging of events: Doppler ultrasound, CT pulmonary angiography or brain MRI document the clot itself.
Treatment options
- Warfarin: The standard long-term anticoagulant after a clot in APS, monitored by INR.
- Direct oral anticoagulants: Generally avoided in high-risk APS, especially triple-positive patients or arterial clots, because trials showed more events than with warfarin.
- Low-dose aspirin and heparin in pregnancy: The established combination for women with APS-related pregnancy loss, started under obstetric and haematology care.
- Risk factor control: Stopping smoking, avoiding oestrogen contraception and treating blood pressure and cholesterol.
- Hydroxychloroquine: Often added when lupus coexists, and sometimes in difficult cases.
When it is urgent
Sudden breathlessness, chest pain, a swollen painful leg, weakness of the face or arm, slurred speech or sudden visual loss need emergency care immediately. Clots in several organs over days (catastrophic APS) are rare but life-threatening. None of these is a reason to board a plane.
Travelling to Türkiye for treatment
Anticoagulation needs steady monitoring near home, so treatment itself does not travel well. What a visit can offer is a properly timed antibody panel, a haematology and rheumatology opinion on how long to continue anticoagulation, or pre-pregnancy planning, sometimes alongside fertility treatment. If you have had a clot, discuss flight precautions with your own doctor first, and bring results of all earlier antibody tests with their dates.
Send your reports, scans and a short history and a Clinic-Y coordinator replies within 24 hours with suitable teams and written, all-inclusive proposals side by side. Reviewing your case is free.
Frequently Asked Questions
I have one positive antibody test. Do I have APS?
Not on that alone. It needs repeating after 12 weeks and must be matched with a clot or a defined pregnancy complication.
Will I need blood thinners for life?
After an unprovoked clot with persistent antibodies, usually yes. The decision is individual.
Can I have a healthy pregnancy?
With aspirin, heparin and close monitoring most women do, though the risk of complications stays above average.
Is IVF safe with APS?
It can be, with a plan for clot prevention agreed before hormone stimulation starts.