Antiphospholipid syndrome (APS) in its typical expression is a systemic autoimmune condition in which antiphospholipid autoantibodies (aPLs) cause recurrent thrombosis in all types of vessels (arteries, veins, and small vessels) and complications in pregnancy, such as spontaneous abortions, pre-eclampsia, etc.
APS : an autoimmune disease
An autoimmune disease is called a disease in which the immune system, whose role is to defend the body against external agents (viruses, bacteria), is over-activated and the immune “response” is directed against the body itself. Antiphospholipid syndrome (APS) is characterized by the presence, in at least two cases within three months of each other, of antibodies called ‘antiphospholipid antibodies’. There are three main types of antiphospholipid antibodies: anti-circulating coagulation antibodies (or lupus antibodies), anti-cardiolipin antibodies and anti-b2-glycoprotein type I (b2GP1) antibodies. Other possible clinical symptoms are mainly cutaneous, neurological, cardiac, and renal. The term ‘primary APS’ or ‘Hughes syndrome’ is used when APS is isolated, i.e. not combined with other autoimmune diseases or specific clinical and biological abnormalities. Otherwise, APS is “associated” with another autoimmune disease, and most often this is systemic lupus erythematosus.
Antiphospholipid antibody syndrome in pregnancy
Antiphospholipid antibody syndrome is caused by the presence of autoantibodies directed against certain proteins, which bind phospholipids, and would normally protect against excessive blood clotting. During a woman’s pregnancy, this syndrome increases the risk of:
- Fetal death
- Pregnancy hypertension
- Delayed intrauterine growth
Antiphospholipid antibody syndrome causes recurrent embryo implantation failures after IVF. Several scientists are proposing the introduction of immunological testing in patients about to attempt to have a child through assisted reproductive techniques as part of a standard protocol for investigating a couple’s infertility.
How is the diagnosis made?
Autoimmune infertility is mainly represented by APS. In the 1980s, women who suffered from this syndrome had a 5-10% chance of carrying a pregnancy to term. Today, the rate of full-term births is 90%. This progress is due to improvements in diagnosis and the treatment available to scientists. From a diagnostic point of view, since 1987, APS has been defined by a combination of clinical and biological criteria:
- Clinical criteria (at least one of which must be present): arterial or venous thrombosis affecting small or large vessels or obstetric morbidity (at least 3 unexplained spontaneous abortions, one or more fetal deaths in more than 10 weeks of amenorrhea or one or more preterm deliveries in less than 34 weeks).
- Biological criteria: serological and hemostasis tests have clarified the data: presence of anti-cardiolipin or anti-β2 glycoprotein 1 IgG or IgM Ac and circulating anticoagulant. Any positive result should be confirmed at 3 months.
Treatment during pregnancy
Appropriate treatment appears to improve the prognosis of pregnancy in these patients. Nevertheless, these women are at increased risk of obstetric accident and require close monitoring. Multidisciplinary monitoring by an experienced team is essential. Women with antiphospholipid syndrome are usually treated prophylactically with anticoagulants and low-dose aspirin during pregnancy and for 6 weeks after delivery.