EDITORIAL COMMENT

The authors have investigated the risk of allograft failure due to the timing of pregnancy after kidney transplantation. Of the 21.814 women aged 15-45 who have received a first kidney-only transplant in the United States Renal Data System, 729 pregnancies were identified using medicare claims. In multivariate analyses, pregnancy in the first posttransplant year was associated with an increased risk of allograft failure from any cause including death (ACGL) (HR: 1.18) and death censored graft loss (DCGL) (HR: 1.25), while pregnancy in the second posttransplant year was associated with an increased risk of DCGL (HR: 1.26). Pregnancy in the third posttransplant year was not associated with an increased risk of ACGL or DCGL. The cause of allograft failure was limited by incomplete data, but changes in immunosuppressant medications and unstable drug levels leading to acute and chronic rejection may be in the causal pathway resulting in graft loss after pregnancy. These results may be useful for physicians providing counseling to women wanting to conceive after transplantation.