Table 1 Inclusion criteria

All women in Australia who gave birth:

a. Between 1 August 2017 and 31 July 2018; AND

b. At least 20 weeks’ gestation and/or at least 400 g birth weight; AND

c. Who present with at least one of the following criteria:

1. A working kidney transplant (all women regardless of kidney transplant function)

2. Receiving any long-term dialysis before conception and continuing any dialysis during pregnancy.

3. Starting any dialysis during pregnancy (any dialysis - either once off, temporary or permanent dialysis)

4. Known pre-conception eGFR < 45 ml/min/1.73m² (known to have a serum creatinine > 130–150 μmol/L before conception, regardless of the serum creatinine reading during pregnancy)

5. Newly identified renal function impairment with any serum creatinine reading of > 150 μmol/L on 2 readings at least 24 h apart during pregnancy