Pregnancy in patients with stage 3-5 CKD: Maternal and fetal outcomes

To investigate pregnancy outcomes and the effects of pregnancy on kidney function in patients with stage 3-5 chronic kidney disease (CKD).

This was a retrospective study. The clinical data of women with pregnancies complicated by stage 3-5 CKD who delivered in the Peking University First Hospital from January 1st, 2013, to December 31st, 2020, were analyzed.

Fifty-three patients with 54 pregnancies were studied. The mean levels of serum creatinine and eGFR in the first trimester were 138.4 ± 76.7 μmol/l and 44.9 ± 13.5 ml/min/1.73 m², respectively. The perinatal mortality rate was 1.92%. The mean gestational age at birth was 35.4 weeks, and the average infant birth weight was 2333 g. The average gestational week at delivery of patients with stage 3a CKD was 36.8 ± 2.1 weeks and there were no adverse neonatal outcomes. Compared with that in early pregnancy, the mean eGFR at 6 months after delivery decreased (52.3 ± 7.3 vs 44.8 ± 10.5 ml/min per 1.73 m², P < 0.01) in patients with stage 3a CKD and urine protein ≥ 1 g/24 h and in patients with stage 3b CKD and urine protein ≥ 1 g/24 h (38.0 ± 2.7 vs. 26.9 ± 10.1 ml/min per 1.73 m², P = 0.03).

The pregnancy outcomes of patients with stage 3a CKD and proteinuria<1 g/24 h are acceptable. Pregnancy accelerates renal function deterioration more significantly among patients with stage 3-5 CKD and urinary protein concentrations above 1 g/24 h.