Pregnancy in renal transplant recipients: the Royal Free Hospital experience

Background: For women with end-stage renal failure of child-bearing age, renal transplantation offers a chance to start a family. Pregnancies in renal transplant recipients involve risks for graft and fetus, and need to be carefully managed. Aim: To identify graft, fetal and maternal outcomes in our patients, and compare our results with those of the large national transplant registries. Design: Retrospective case-note review. Methods: We assessed the outcomes of 48 pregnancies in 24 renal transplant recipients. Obstetric data and renal parameters were examined in 27–30 pregnancies that progressed to delivery. Results: Mean time from transplantation to pregnancy was 6.5 years, with an unfavourable outcome in patients who conceived within 1 year. There was a 41% incidence of fetal growth restriction (FGR), and 33% of infants were small for gestational age. FGR was associated with maternal hypertension, a pre-pregnancy serum creatinine (SCr) ≥ 133 μmol/l (1.5 mg/dl), calcineurin inhibitors and the use of cardioselective β blockers. Two patients with pre-pregnancy SCr > 200 μmol/l lost their grafts within 3 years of delivery. A permanent significant decline in graft function occurred in 20%, by 6 months post delivery. Discussion: FGR with SGA infants occurs frequently. Atenolol should be avoided in pregnancy and Metoprolol should not be combined with calcineurin inhibitors. Pregnancy appeared to have a deleterious effect on graft function in patients with SCr > 155 μmol (1.75 mg/dl). Patients with pre-pregnancy SCr 200 μmol/l are at greatest risk.