Global Data Support Successful Pregnancy Outcomes in Kidney Transplant Recipients

Data from an analysis of 3 registries across continents show consistent maternal, neonatal, and long-term graft outcomes, confirming that pregnancy can be successful after kidney transplantation with careful monitoring.1

The comparative analysis of registries from the Netherlands, Australia/New Zealand, and the United States attests to the possibility of successful post-kidney-transplantation pregnancies despite elevated risks, reaffirming the importance of close clinical surveillance of mother, fetus, and graft. Further global data harmonization is important to support clinicians managing these high-risk pregnancies.

“Pregnancy outcomes appear consistent across the registries, despite the differences in population size and methodology,” wrote study investigator Styliani Giapoutzidou, MSc, a student researcher in obstetrics and nephrology at the University of Groningen, and colleagues.1 “Pregnancy post-kidney transplant recipients are classified as high-risk. However, the risk can be moderated through advance planning and close monitoring.”

Following kidney transplantation, fertility typically returns quickly to levels sufficient for conception. Female patients are generally advised to wait ≥1 year before attempting to become pregnant. The increasing frequency of pregnancies in kidney transplant recipients calls for improved understanding among clinicians and patients and an expansive effort to collect comprehensive outcome data.2

To address this gap in research, investigators reviewed data from 3 major registries.

• Pregnancy After Renal Transplantation OUTcomes (PARTOUT), retrospective analysis of pregnancies 1971–2017 in the Netherlands.
• The Australia and New Zealand Dialysis and Transplant Registry (ANZDATA), annual surveys of all KTR parenthood events since 1968.
• The Transplant Pregnancy Registry International (TPRI), a US/international voluntary registry of pregnancies since 1991.

Investigators noted both alignment and methodological differences across PARTOUT, ANZDATA, and TPRI. Mean gestational age was approximately 35 weeks in all registries, while mean birth weight was 2383 g for PARTOUT, 2360 g (median) for ANZDATA, and 2551 g for TPRI. Regarding pregnancy outcomes, PARTOUT reports live births only after 20 weeks’ gestation, whereas ANZDATA and TPRI also include miscarriages before 20 weeks. All 3 registries define stillbirth as occurring after 20 weeks. Ectopic pregnancies are reported only by TPRI, while pregnancy terminations are reported by ANZDATA and TPRI.

Across the 3 registries, reported live birth rates ranged from 75–95%. Long-term graft outcomes were generally consistent, with graft loss occurring in 23% of PARTOUT recipients at a median of 6.44 years post-delivery, 27% of ANZDATA participants at a median follow-up of 8.08 years, and 33% of TPRI participants at a median follow-up of 14.4 years. These findings highlight the importance of ongoing post-pregnancy monitoring of kidney function in transplant recipients, even several years after delivery.1

“What is the next step? Establishing global datasets with increased data acquisition should enable improved identification of predictors of pregnancy and newborn complications and should include data from populations potentially under-represented in the existing registries,” investigators concluded.1

Study investigators proposed the creation of a future global dataset focused on standardising core variables, aligning definitions across registries, and securely pooling deidentified data. Collaborators would define research questions, outcomes, and analyses upfront, establish inclusive authorship, and create sustainable processes for ongoing updates. This approach aimed to strengthen evidence and improve guidance for clinicians managing high-risk pregnancies in kidney transplant recipients.

References

1. Giapoutzidou S, Hewawasam E, Gosselink ME, et al. Pregnancy after kidney transplantation: global insights based on registry data from three continents. Journal of Nephrology. Published online November 22, 2025. doi:https://doi.org/10.1007/s40620-025-02451-x

2. Pregnancy, Fertility, and Babies after a Kidney Transplant. National Kidney Foundation. Published November 8, 2024. https://www.kidney.org/kidney-topics/pregnancy-fertility-and-babies-after-kidney-transplant