Antiphospholipid Syndrome (APS)

By BSc, MSc (embryologist) and BA, MA (fertility counselor).
Last Update: 10/31/2014

Anitphospholipid syndrome (APS) is a sickness that affects the clotting mechanisms and can cause problems during pregnancy, provoking an insufficient growth of the foetus or high blood pressure.

It is included under thrombophilia, which comprises all the illnesses, in which there’s a tendency to the thrombus formation in blood vessels. It’s produced due to the presence of antibodies in blood that alter the phospholipids mechanism, substances that are needed for a proper blood flow and clotting.

Thrombus due to APS

It is also known as antiphospholipidic syndrome and many people who suffer from it may not show any symptoms. Actually, 2% of women who have to endure it don’t manifest any symptoms. It’s neither contagious nor a terminal sickness, but it has to be taken into account during pregnancy, due to the impact that it can have on foetal development.

The most common complications during pregnancy are usually: thrombosis, abortions, delayed foetal growth, preterm deliveries and severe high blood pressure.


Its identification plays a vital role in women with a history of thrombosis, preterm deliveries, abortions and recurring foetal deaths with unknown cause. It’s also crucial in women that present high blood pressure or manifest or have a history of inappropriate intrauterine foetal growth.

The diagnosis requires of two criteria, one clinic and one coming from the laboratory, but they don’t have to take place at the same time. Actually, what’s recommended is that there’s a period of time of 12 months between both of them but inferior to 5 years.

Clinic criteria include vascular thrombosis (confirmed according to objective validated criteria) and gestational morbidity. Under this latter criterion are included: normal embryos abortion before the tenth pregnancy week (three or more consecutive abortions), foetal death with unknown cause over the tenth gravidity week in normal foetuses with a normal medically proved morphology, or preterm babies born before the 34th pregnancy week as a consequence of a placental insufficiency but presenting a normal morphology.

Origin antiphospholipidic syndrome

The laboratory criterion is the presence of one of the following antibodies: lupus anticoagulant (LA), anticardiolipin antibodies (ACA) and anti-β-2 glycorpotein-I antibodies.

Clinical manifestations

Clinical manifestations will vary depending on the place and size of the thrombosis, as well as the possible embolisation of other organs. The most frequent are:

  • Thrombosis: it´s the most common and it can affect any vessel of the organism. It’s usually recurring and frequently in the same system where it once was. In low risk patients it is an evident sign of the syndrome. It’s common that the illness will appear in situations where the risk increases, such as pregnancy, treatment with contraceptive pills and puerperium (postnatal period).
  • Venous thrombosis: as in the previous case, its appearance in low risk individuals is an evident sign of the syndrome. This is the most common type, especially in the lower body.
  • Arterial thrombosis: they aren’t as common as the venous ones (30% of the cases are arterial thrombosis and 70% are venous thrombosis) and they are usually located in the brain.

However, the manifestations mentioned above are not the only ones. There’s also: thrombopenia (mild or moderate plateletopenia), livedo reticularis (refers to a blue-reddish skin discoloration, which is severe in cases of APS), and neurological disorders (such as migraine, transverse myelitis, multi-infarct dementia or chorea).

Patients may also develop severe APS, characterised by a severe generalised thrombosis, with a mortality rate of 50%.

Manifestations during gravidity

Recurring abortion is the sickness’ most common manifestation during pregnancy and especially during the second and third trimester. Other manifestations are: delayed foetal development, oligohydramnios, Doppler disruptions, hypoxias and preeclampsia.

Generally all these manifestations provoke preterm deliveries (30% of the cases).

Medical check-up pregnant women with APS


The possible situations in case of APS are so different that there’s polemic about its treatment. Only 30% of the patients with antibodies and no clinic manifestation develop the syndrome. In these cases prophylaxis wouldn’t be appropriate. Nonetheless, if there’s thrombosis, arterial or venous, the need of anticoagulant medicines is evident, be it punctual or of undetermined duration, depending on the recurring risk.

The usage of immunosuppressive medication, steroids, anti-platelet medication... is even more questioned. In the case of cerebral thrombosis, the simultaneous prescription of heparin and steroids, along with azathioprine or cyclophosphamide is recommended.

Aspirin in low doses can be prescribed to pregnant women ever since the beginning of gravidity, if the analysis of antiphospholipid antibodies is positive. Moreover, if there’s a history of thrombosis, abortions or foetal deaths, the usage of prednisone combined with aspirin and subcutaneous heparin is recommended. There are also some alternatives, such as treatments based on plasma exchange and intravenous immunoglobulin in high dose, etc. The treatment chosen will vary depending on the history of the patient, the risks associated with the situation and the specialist prescribing the treatment.

It’s highly important that there’s a multidisciplinary medical control of these patients, with specialists in obstetrics, haematology, internal medicine or rheumatology, and all of them experienced in handling with the syndrome. There must also be a good communication between all the specialists. The patient must be informed of the obstetric and thrombotic risks of the situation and she must be informed about the fact that it’s a cause of foetal loss. Luckily, if a treatment is followed, 80% of the cases result in delivery.

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 Neus Ferrando Gilabert
Neus Ferrando Gilabert
BSc, MSc
Bachelor's Degree in Biology from the University of Valencia (UV). Postgraduate Course in Biotechnology of Human Assisted Reproduction from the Miguel Hernández University of Elche (UMH). Experience managing Embryology and Andrology Labs at Centro Médico Manzanera (Logroño, Spain). More information about Neus Ferrando Gilabert
Adapted into english by:
 Sandra Fernández
Sandra Fernández
Fertility Counselor
Bachelor of Arts in Translation and Interpreting (English, Spanish, Catalan, German) from the University of Valencia (UV) and Heriot-Watt University, Riccarton Campus (Edinburgh, UK). Postgraduate Course in Legal Translation from the University of Valencia. Specialist in Medical Translation, with several years of experience in the field of Assisted Reproduction. More information about Sandra Fernández

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