Pregnancy in kidney transplant recipients: effects on mother and newborn

Pregnancy is currently considered yet another benefit of kidney transplantation, though doubts still exist concerning the effects of transplantation on the mother and the fetus.

We undertook a retrospective study analyzing 24 pregnancies in 20 kidney transplant recipients between 1986 and 2010. Evaluation was made of different variables related to renal function, both during the pregnancy and afterward, as well as other factors related to the birth and the status of the newborn.

The mean age of the kidney transplant recipients was 29 ± 5 years, and the mean time since transplantation was 4.5 years (range = 0.8-12). At the time of pregnancy, the glomerular filtration rate was 59 ± 15 mL/min. Twelve recipients had well-controlled hypertension; none had proteinuria. Renal function and proteinuria remained stable during the pregnancy. There was a significant increase in blood pressure at the end of the pregnancy. It was necessary to raise the dose of calcineurin inhibitor to maintain target levels. No acute rejection episode was observed. One patient had gestational diabetes and two showed preeclampsia. Pregnancy reached term in 20 cases; there were four miscarriages. Delivery was at 36.9 weeks (range = 34-41) and the newborn weight, 2.7 kg (range = 1.5-3.6). One patient had a miscarriage at week 22 and succumbed due to a cardiac arrest during induction of the delivery. Eighteen babies were born healthy; two died.

Pregnancy in kidney transplant recipients is safe if the renal function is adequate before the pregnancy without proteinuria but with a well-controlled blood pressure. In these cases, the maternal complications were similar to those among general population; we detected no increased risk of graft loss.