Transplantation and Mortality in Women After Delivering on Hemodialysis

Rates of successful pregnancies among women with end-stage kidney disease (ESKD) on hemodialysis (HD) are increasing, however the risk of preeclampsia and preterm delivery remain high. The association of delivery on HD with subsequent transplantation and mortality are unknown.

Using United States Renal Data System (USRDS) data, females treated with HD who delivered an infant between 2002 and 2019 were identified from ICD-9/10-CM codes and matched up 1:4 by age, vintage, race and ethnicity, and diabetes as primary cause of ESKD, to contemporary females on HD who did not deliver. We assessed transplantation and mortality rates over time after delivery. Cox proportional hazards models were fit to compare transplant and mortality rates between delivering and nondelivering women. All models were adjusted for age, vintage, body mass index (BMI), race, Hispanic ethnicity, incident comorbidities, rural-urbanicity, nephrology care pre-ESKD, Medicare insurance, and prior transplant history; patient waitlist status and panel reactive antibody (PRA) values were also adjusted in the transplant models.

One thousand one hundred nine delivering females were matched to 4404 nondelivering females. Unadjusted transplantation and mortality rates for delivering versus nondelivering females were 6.0 versus. 8.6 and 4.5 versus 7.2 per 100 patient-years, respectively. In adjusted models, the hazard ratios (HRs) (95% confidence interval [CI]) for transplant and mortality were 0.78 (0.69-0.88, P < 0.0001) and 0.69 (0.64-0.74; P < 0.0001), respectively, in delivering compared to nondelivering females.

Although pregnancy on HD has immediate risks of maternal morbidity, infant delivery was associated with a lower risk of long-term maternal mortality. Residual confounding may explain superior survival of delivering versus nondelivering females; however, persistently lower transplant rates in delivering females warrant further research.