Scenario

A 30 year old woman is referred to the obstetric medicine clinic. She is eight weeks pregnant according to the timing of her last menstrual period. She has systemic lupus erythematosus (SLE), diagnosed in 1998. The disease has affected predominantly her joints, but she did have a related nephritis flare in 2000. She has never had a venous or arterial thromboembolus. Her last SLE flare was three years ago during her last pregnancy, and it was confined to her joints; her baby daughter then (now 3 years old) had been delivered normally after induction of labour at 36 weeks' gestation. She had gestational diabetes from 24 weeks in her last pregnancy, but an oral glucose tolerance test six weeks postnatally was normal, confirming true gestational diabetes.

Her current medications include azathioprine 125 mg once daily, prednisolone 4 mg once daily, hydroxychloroquine 200 mg twice daily, and aspirin 75 mg once daily.

She is feeling well, with no joint pains. Her blood pressure is 115/65 mm Hg, urine analysis was negative for blood and protein, and an oral glucose tolerance test was normal. Her latest serology shows that she is positive for antinuclear antibodies, negative for double stranded DNA (although this has been positive in the past), positive for anticardiolipin antibody IgG, positive for anti-Ro antibody, and her complement 3 and 4 levels are in the normal range. Renal function is normal (serum creatinine concentration 67 µmol/l).