Kidney graft function before pregnancy as a predictor of graft, maternal and fetal outcomes in pregnant renal transplant recipients

Objectives Maternal and fetal complications can occur in pregnant kidney transplant recipients. Since these are high-risk pregnancies, they require a multidisciplinary follow-up to prematurely detect adverse events. Identifying factors that would affect fetal, maternal and graft outcomes is essential to further stratify the risk of pregnant kidney transplant recipients. Methods All pregnancies in kidney transplant recipients followed in a single center for 30 years were included. Data included previous transplant information and blood and urine tests performed before pregnancy. Impact of graft function on fetal, maternal and graft outcomes was evaluated. Results There were 41 pregnancies among 34 patients. Mean gestational age of 35 +/- 3 weeks. Caesarean section was performed in 69.4% of patients. Five pregnancies were unsuccessful (12.2%). Four patients suffered an acute graft dysfunction (9.8%) and 12 (29.3%) had a serious maternal hypertensive disorder (preeclampsia, eclampsia or HELLP syndrome). Graft function before pregnancy showed significant correlation with adverse outcomes. Conclusions A proteinuria >669 mg/g, serum creatinine >1.75 mg/dL and glomerular filtration rate <36.2 mL/min/1.73 m(2) before pregnancy were correlated to graft dysfunction during pregnancy. Similar values of proteinuria were also associated with a risk of maternal hypertensive disorders and pregnancy failure. Therefore, in patients with proteinuria and graft dysfunction, follow-up should be stricter to quickly detect complications.