Predictors for graft survival after pregnancy in kidney transplant recipients

M.C. van Buren, A.T. Lely, J. van de Wetering

Wednesday 13 march 2019

16:10 - 16:20h at Tropentheater

Categories: Best abstracts, Parallelsessie

Parallel session: Parallelsessie VIII – Best abstracts II

Background: Pregnancy after kidney transplantation (KT) is increasing during the last decades. Generally, pregnancy outcomes after KT are good. However, there is a high risk of gestational hypertension, preeclampsia and dysmaturity. Less is known about the effect of pregnancy on the kidney transplant. For counselling prior to pregnancy it is important to know risk factors for graft loss, and consequently recurrence to dialysis or re-transplantation, after pregnancy.

Methods: We conducted a nationwide retrospective multi-center cohort study in women with a pregnancy (>20 weeks) after KT in the Netherlands from 1960 to 2017. Data on transplantation, pregnancy and pregnancy outcomes were collected from health records. To explore predictors associated with graft survival after pregnancy we performed a Cox Regression Analysis.

Results: We could include 167 KT women with 244 pregnancies of which 96% ended in a live birth. 181 (74%) pregnancies were with the first kidney, 53 (22%) pregnancies were with a pre-emptive transplantation. Graft loss was present after 62 (25%) pregnancies at a median time after delivery of 6 yrs (range 0-30 yrs). In 20 (8%) pregnancies graft loss occurred within 3 years after delivery. In 34 (50%) women the cause of graft loss was rejection. In regression analysis preconceptional creatinine (p 0.00), gestational age of the pregnancy (p 0.02), postmortal donor transplantation (p 0.00) and pregnancy after first KT (p 0.02) were associated with better graft survival censored for death. Time between KT and delivery, preeclampsia and more pregnancies after KT were not associated with worse graft survival.

Conclusions: A worse pre-conceptional renal function, first kidney and a shorter gestational age are associated with a higher risk of graftloss in women with a KT. In contrast with the graftsurvival results in the general KT population, KT with a postmortal donor was associated with better graft survival after pregnancy. This may be the result of selection in the early days of transplantation, where pregnancy was only advised to women with relatively good kidney function. Further analysis of the individual slopes of eGFR pre- and post-pregnancy will be necessary to identify predictors for worse graft outcome after pregnancy in KT recipients. Although, in general pregnancy outcomes after KT are good, we have to realise that a significant proportion of women will have to be on dialysis or re-transplanted again while their children are still young.