Lupus pregnancy: is heparin a risk factor for osteoporosis?

Regulation of calcium homeostasis during pregnancy is complex. Clinically s ignificant bone mass loss is infrequent; however a subset of women may deve lop symptomatic osteoporosis related to pregnancy. Lactation is a period of special risk for bone loss. Whatever the effect of heparin on bone loss, v ertebral fractures are rare in women treated with heparin during pregnancy, Low molecular weight heparins may have a less deleterious effect on bone t han unfractionated heparin. Women with autoimmune diseases, particularly th ose with lupus and/or the antiphospholipid syndrome may receive heparin thr oughout pregnancy. Corticosteroids must be reduced as much as possible in t hese women, and calcium plus vitamin D are recommended. Finally, indication s for heparin use must be clearly justified and advice regarding breastfeed ing must be offered.