Immunosuppression with Tacrolimus Improved Reproductive Outcome of Women with Repeated Implantation Failure and Elevated Peripheral Blood Th1/Th2 Cell Ratios

ProblemWe evaluated the clinical efficacy of immunosuppressive treatment with tacrolimus for repeated implantation failure (RIF) patients who have elevated in T helper (Th1)/Th2 cytokine producing cell ratios. Method of studyThis was a prospective cohort study of treatment for RIF patients (n=42) with elevated peripheral blood Th1 (CD4(+)/IFN-(+))/Th2 (CD4(+)/IL-4(+)) cell ratios at the Sugiyama clinic between November 2011 and October 2013. Twenty-five patients were treated with tacrolimus (treatment group) and 17 received no treatment (control group). Treatment group received tacrolimus 2days before embryo transfer and continued until the day of the pregnancy test, for a total of 16days. The daily dose of tacrolimus (1-3mg) was determined based on the degree of the Th1/Th2 cell ratio. ResultsThe clinical pregnancy rate of the treatment group was 64.0%, which was significantly higher than that of the control group (0%) (P<0.0001). In the treatment group, the miscarriage rate was 6.3%, the live birthrate was 60.0% (P<0.0001). There was no significant side-effect from tacrolimus in treatment group. No one developed obstetrical complications during pregnancy. ConclusionAn immunosuppressive treatment using tacrolimus improved pregnancy outcome of repeated implantation failure patients with elevated Th1/Th2 ratios.