Chronic kidney disease (CKD) is considered to complicate 1 in every 750 pregnancies with Stages 3–5 CKD. CKD may result in risk factors including preterm delivery, fetal growth restriction and a decline in maternal renal function.

A study was carried out among women with CKD Stages 3–5 after 20 weeks gestation in different tertiary renal centres between 2003 and 2017. The impact of CKD stage 3-5 on pregnancy and the factors predicting adverse effects were monitored. The study inferred that the live birth rate was 98% among 178 pregnancies in 159 women, including 43 women with renal transplants. Among these 56% of babies were born preterm. The study also showed that chronic hypertension was the main cause of preterm births and the rate doubled 20% to 40% among these women. Also, pre-or early pregnancy proteinuria enhanced the risk of babies being born who were underweight, having weight below 10th centile. 

A considerable reduction was observed in the glomerular filtration rate (eGFR) between pre-pregnancy and post-partum values. Pregnant women with chronic hypertension and with a gestational fall in serum creatinine less than 10% of pre-pregnancy concentrations showed a greater decline in pregnancy-associated renal function. The effect of pregnancy was found to be equivalent to 1.7, 2.1 and 4.9 years of pre-pregnancy renal disease in CKD Stages 3a, 3b and 4–5, respectively. Most women with renal transplants had CKD Stage 3 and more stable renal function prior to pregnancy.

Conclusions: Thus it was concluded that chronic kidney disease stage 3-5 had a significant impact on pregnancy outcomes. It resulted in preterm delivery, low birth weight and loss of maternal renal function. Also, chances of dialysis or transplantation advance under such circumstances. Hence, pre-pregnancy counselling, antenatal surveillance and the postnatal management of women with CKD stage 3–5 become essential. 

References:

1. Kate Wiles, Philip Webster, Paul T Seed, Katy Bennett-Richards, Kate Bramham, Nigel Brunskill, Sue Carr, Matt Hall, Rehan Khan, Catherine Nelson-Piercy, Louise M Webster, Lucy C Chappell, Liz Lightstone, The impact of chronic kidney disease Stages 3–5 on pregnancy outcomes, Nephrology Dialysis Transplantation, 2020, , https://doi.org/10.1093/ndt/gfaa247.