Long-Term Effects of Pregnancy on Renal Graft Function in Women After Kidney Transplantation Compared With Matched Controls

Abstract Background An important benefit associated with kidney transplantation in women of child-bearing age is increased fertility. We retrospectively evaluated the maternal and fetal complications and evolution of graft function associated with 22 pregnancies post–kidney and kidney-pancreas transplantation, compared with controls without pregnancy post-transplantation, who were matched for gender, year of transplantation, type of donor, age at transplantation, number of transplants, type of transplant (kidney vs kidney-pancreas), and cause of native kidney failure, as well as for renal parameters including serum creatinine and urine protein excretion 1 year before delivery. Results The mean age at time of transplantation was 22.32 (range, 19.45–33.1) years. The mean interval between transplantation and delivery was 75.7 (range, 34–147.8) months. Main maternal complications were pre-eclampsia in 27.3%. The main fetal complications included delayed intrauterine growth (18.2%), preterm deliveries (89.4%), and one death at 3 days postdelivery. The mean serum creatinine level pre-pregnancy was 1.17 (range, 0.7–3.1) mg/dL. Graft failure was higher in the pregnancy group (6 vs 3) but did not differ statistically from the control group, and was associated with creatinine pre-pregnancy (odds ratio [OR], 1.71; 95% confidence interval [CI], 1.15–3.45; P  = .04), age at transplantation (1.13 [1.03–1.21]; P  = .032), and time of follow-up (2.14 [1.27–2.98]; P  = .026). Delta serum creatinine was not different in both groups: 1.05 ± 0.51 versus 0.99 ± 0.92 mg/dL, study versus control group, respectively ( P  = .17). Conclusion Pregnancy after kidney transplantation is associated with serious maternal and fetal complications. We did not observe a significantly increased risk of graft loss or reduced graft function in comparison with recipients with similar clinical characteristics.