Which one of the following statements concerning the phospholipid antibody syndrome in pregnancy is true?  

Women in pregnancy, with a history of serious thrombotic episodes and high levels of antiphospholipid antibodies, are treated with aspirin and low-dose of heparin.

95% of pregnant women with anti-phospholipid antibodies will suffer a miscarriage.

Immunosuppression is used to reduce the level of antibody titres to achieve a successful pregnancy.

Infants of mothers with antiphospholipid antibodies have congenital heart block.

Antiphospholipid antibodies are present in 50-60% of all cases of deep vein thrombosis.