Article Text
Abstract
Background Chronic kidney disease (CKD) estimated to affect 3% of all pregnancies, and this is expected to rise due to increasing prevalence of maternal age and obesity. Previous studies have shown varying results regarding pregnancy outcomes across different renal conditions. This study aimed to assess the association between pre-pregnancy CKD and the risk of adverse pregnancy outcomes. We further evaluate the associations among women with congenital renal disease, renal failure or kidney transplantation.
Methods This population-based cohort included women who had singleton births in Sweden between 1982 and 2012. Using data from the Medical Birth Register, a total of 2,778,596 babies were born to 1,418,274 mothers. We identified 10,885 babies who were born to women with pre-pregnancy CKD (classified according to ICD-8, ICD-9 and ICD-10). Outcome measures included pre-eclampsia (PE), emergency and elective caesarean sections (CS), spontaneous preterm birth (PTB<37 weeks’ gestation), medically indicated PTB, stillbirth and small for gestational age (SGA). Multivariate logistic regression models were conducted using Stata 16 and adjusting for several socio-demographic and perinatal confounders.
Results Compared to women without CKD (reference group), the odds of the following outcomes were higher among women with pre-pregnancy CKD: PE adjusted odds ratio [aOR (95% confidence intervals)]: [1.75 (1.59, 1.92)]; emergency CS [1.37 (1.27, 1.47)]; elective CS [1.67 (1.55, 1.80)]; spontaneous PTB [1.29 (1.16, 1.44)]; medically indicated PTB [1.92 (1.74, 2.11)] and SGA [1.32 (1.19, 1.47)]. Moreover, the odds were higher for women with renal failure and kidney transplantation, compared to women without CKD. Additionally, women with congenital renal disease had higher odds of PE [aOR: 7.99 (4.97, 12.8)] and medically indicated PTB [6.71 (3.82, 11.8)].
Conclusion Despite advances in antenatal care, the risk of adverse pregnancy outcomes among women with CKD are higher compared to women with no CKD. Planning for pregnancy should be optimized before conception in women with kidney failure or who have had a kidney transplantation.