Immunosuppressants pose challenge in pregnancy: balancing immunosuppression with the health of the woman and fetus requires team approach.(Obstetrics)

WASHINGTON -- Balancing immunosuppression in a pregnant allograft transplant patient with the health of the woman and her fetus requires a team approach between high-risk obstetricians and transplant physicians, according to one expert speaking at a meeting sponsored by the National Kidney Foundation.

"Pregnancy in the transplant recipient, aside from the issue of renal dysfunction, poses a unique set of considerations, and that's because of immunosuppressants," said Michelle A. Josephson, M.D., of the University of Chicago.

None of the immunosuppressants used for transplantation--cyclosporine, tacrolimus, azathioprine, steroids, rapamycin, and mycophenolate mofetil--are rated pregnancy category A, using the Food and Drug Administration classification system. In fact, most are rated category C, meaning there are no data on their use in humans during pregnancy. "All medications used to prevent rejection cross the maternal-placental interface," she pointed out.

Despite the lack of data and potential risks, a consensus group convened in 2003 by the Women's Health Committee of the American Society of Transplantation recommended immunosuppression be maintained during pregnancy to avoid rejection.

Graft rejection can be difficult to discern during pregnancy because serum creatinine levels are low during this period, and small changes can be missed, Dr. Josephson said. In addition, abnormalities that turn up on liver function tests can have a number of etiologies. For these reasons, graft dysfunction during pregnancy warrants appropriate investigation--by biopsy if necessary.

"If rejection occurs, it can be treated with steroids," Dr. Josephson recommended. Inadequate immunosuppression, graft instability, and rejection likely affect the graft prognosis. However, age, number of allografts, and repeat pregnancies don't seem to impact graft function and prognosis.

The consensus group also agreed that a high-risk obstetrician and a transplant physician should manage pregnant transplant patients. Obstetricians should optimize maternal health, maintain normal glycemia, ensure adequate fetal growth, and anticipate preterm birth. The transplant physician should ensure maintenance of graft function and aggressively manage hypertension and preeclampsia. Cesarean section is not indicated except for standard obstetric reasons.