A Rho-incompatible pregnancy induces anemia in the fetus and can ultimately lead to fetal hydrops and intrauterine fetal death. A patient who had experienced recurrent implantation failures following a first successful delivery finally succeeded in achieving a second pregnancy via the use of tacrolimus. The second pregnancy was Rho-incompatible. During the course of the pregnancy, the treatment with tacrolimus was continued because the patient's T helper type 1 (Th1) cell population remained at a high level following the achievement of pregnancy. The dose was increased during pregnancy because of the elevated Th1 cell count at 28-week gestation. Tacrolimus maintains a stable state of pregnancy while simultaneously suppressing the production of anti-D antibodies. Using tacrolimus, we succeeded in resolving the infertility and inhibition of antibody production in this case of an alloimmunized pregnancy.
Keywords: Alloimmunized pregnancy; anti-D antibody; infertility; tacrolimus.