Pregnancy after living kidney donation, a systematic review of the available evidence and a review of the current guidance

American Journal of Transplantation. 2022;22(10):2360-2380

Abstract

Understanding and communicating the risk of pregnancy complications post-living kidney donation is imperative as the majority of living kidney donors (LKD) are women of childbearing age. We aimed to identify all original research articles examining complications in post-donation pregnancies and compared the quality and consistency of related guidelines. We searched Embase, MEDLINE, PubMed, society webpages and guideline registries for English-language publications published up until 18/12/2020. Ninety-three articles were screened from which 16 studies were identified, with a total of 1,399 post-donation pregnancies. The outcome of interest, post-donation pregnancy complications, was not calculable, and only a narrative synthesis of the evidence was possible. The absolute risk of pre-eclampsia increased from ~1-3% pre-donation (lower than the general population) to ~4-10% post-donation (comparable to the general population). The risks of adverse foetal and neonatal outcomes were no different between post-donation and pre-donation pregnancies. Guidelines and consensus statements were consistent in stating the need to inform LKDs of their post-donation pregnancy risk, however the depth and scope of this guidance was variable. Whilst the absolute risk of pregnancy complications remains low post-donation, a concerted effort is required to better identify and individualise risk in these women, such that consent to donation is truly informed.

CET Conclusion

Reviewer: Mr Simon Knight, Centre for Evidence in Transplantation, Nuffield Department of Surgical Sciences University of Oxford
This systematic review summarises the literature and guidelines relating to pregnancy following living kidney donation. The authors identified 16 studies reporting on 1399 post-donation pregnancies. Whilst the risk of pre-eclampsia increased post-donation, it is in keeping with an unselected general population. No difference was found in risk of other pregnancy or foetal complications. Guidelines were found to be generally consistent in advice. Methodology appears good, with well-described searches across a number of databases and screening by 3 reviewers. Risk of bias was assessed with the Robins-I tool and found to be low-moderate in most studies. Of note, studies were published over a long period (35 years) so it is perhaps not clear how relevant results of early studies are to today’s practice. Overall, the authors graded the certainty of evidence in risk of hypertension and pre-eclampsia as “low” and for other foetal outcomes as “very low”, reflecting the quality and size of the underlying evidence. This paper provides a very good summary of the evidence (and limitations thereof) regarding post-donation pregnancy.

Study details

Aims : The aim of this study was to identify all available evidence investigating pregnancy complications post-living kidney donation, and to compare the quality and consistency of guidelines focusing on pregnancy in living kidney donors.
Interventions : A literature search was conducted on Embase, PubMed, MEDLINE, society webpages and guideline registries. Three independent reviewers performed the initial screening of study titles and abstracts. Eligibility assessment of full-text articles and data extraction were carried out by two independent reviewers. The methodological quality of the included studies were assessed using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool.
Participants : 16 studies were included in the review.
Outcomes : The main outcomes of interest were post-donation pregnancy complications, and the risk of adverse maternal, fetal and neonatal outcomes.
Follow up : N/A

Metadata

Funding : Non-industry funding
Publication type : Systematic Review
Organ : Kidney
Language : English
Author email : maria.pippias@bristol.ac.uk