Hi EJE, sorry for the mix-up; I know you've probably seen this already but thought I'd post it in case it was needed by anyone:

Lupus anticoagulant
From Wikipedia, the free encyclopedia

Lupus anticoagulant is an autoimmune disorder caused by antibodies that bind to phospholipids and proteins associated with the cell membrane. This antibody has the peculiar nature of causing a delay in coagulation in laboratory tests (the partial thromboplastin time) while clinically predisposing for thrombosis. It is also known as lupus antibody, LA and lupus inhibitor. Together with anticardiolipin antibodies, LA causes the bulk of antiphospholipid syndrome.

Although it is named "lupus anticoagulant," this is a misnomer. Most patients with the antibody do not have lupus erythematosus, and only a small proportion will proceed to develop this disease (which causes joint pains, skin problems and renal failure, amongst other complications). Furthermore, this antibody is not associated with anticoagulation, but rather is associated with thrombosis and habitual abortion (repeated miscarriage). Various other symptoms (e.g. migraine and rash) may be reported, but these are very non-specific, and it is uncertain whether these are caused by the antibodies at all.

Diagnosis is initially with a laboratory test termed the dilute Russell viper venom time. Mixing studies then confirm the presence of lupus anticoagulant.

There is no specific treatment, but miscarriages can be prevented with the administration of low molecular weight heparins (LMWHs), and thrombosis is treated with anticoagulants (LMWHs and warfarin).
So it's not lupus, and it's nothing to do with coagulation... how dumb.

Anyway, Heparins:
Heparin
Heparin initiates anticoagulation rapidly, but has a short duration of action. It is now oftern referred to as being standard or unfractioned heparin to distinguish it from the low molecular weight heparins, which have a longer duration of action. For patiends at high risk of bleeding, heparin is more suitable than LMW heparin because its effet can be terminated rapidly by stopping the infusion.

Low Molecular Weight Heparins
Bemiparin, certoparin, dalteparin, enoxaparin, reviparin, and tinzaparin are low molecular weight heparins. (No info on preventing miscarriage in this, so won’t type it all out.)

Side-effects: haemorrhage, skin necrosis, thrombocytopenia, hyperkalaemia, hypersensitivity reactions (inclufing urticaria, angioedema, and anaphylaxis); osteoporosis after prolonged use (and rarely alopecia).
Please note that these side-effects are not at all common - sadly the BNF book I have didn't give any figures, but I can't think of anyone who's had a problem with heparin, though saying that it's not a drug we use a lot in endocrinology. Please note that Warfarin is contra-indicated in pregnancy (over here, at least), so you really shouldn't be on that if you're TTC.

Hope that was of a bit more help for you!