Objective: To measure the incidence and outcomes of pregnancies in renal transplant (RT) patients and to identify risk factors of adverse pregnancy outcomes.
Methods: We conducted a population-based retrospective cohort study using the United States Nationwide Inpatient Sample from 2003-2010. The incidence of pregnancies in women with RT was measured and logistic regression analysis was used to estimate the adjusted effect of RT on maternal and fetal outcomes.
Results: We identified 375 deliveries in patients with a RT among 7094300 births for an overall incidence of 5.3 cases per 100000 births over 8 years. Maternal complications, including preeclampsia OR=9.87 (7.76, 12.55) and blood transfusion OR=2.29 (1.69, 3.12) were more common in women with RT as compared to in women without. RT pregnancies were also complicated by an increased risk of preterm birth OR=4.65 (3.72, 5.81), intrauterine fetal death OR=3.67 (1.89, 7.15) and fetal congenital anomalies OR=5.28 (2.81, 9.90). Among women with RT and pre-existing hypertension, the risk of intrauterine growth restriction (IUGR) was considerably increased from 4.3% to 21.8%, OR=3.79 (1.67, 8.62).
Conclusion: Pregnancies in RT patients are associated with an increased risk of maternal and fetal morbidities. Among women with RT, pre-existing hypertension strongly increases the risk of IUGR.
Keywords: Fetal outcomes; maternal outcomes; pregnancy; renal transplant; risk factors.