Table 1 Demographic data of 67 mothers, 92 pregnancies and 95 offsprings

Course of kidney disease and pregnancy of the mothers:

 Duration of dialysis (yrs)

2.85 ± 2.37 (0–9)

 Preemptive transplantation (%)

n = 4 (5.97)

 Living-transplant (%)

n = 23 (34.33)

 Transplantation before the age of 18 years (%)

n = 14 (20.9)

 Age of the mothers at transplantation (yrs)

23.72 ± 7.18 (6.5–35)

 Post-transplant hypertension pre-pregnancy (%)

n = 52/71 (73)

 Age of the mothers at conception (yrs)

29.6 ± 4.7 (15–39)

 Time from transplantation to conception (yrs)

6.51 ± 5.33 (0.5–24.75)

 Transplant age at conception including donor age (yrs)

39.75 ± 14.6 (9.5–67.2)

Number of transplants:

 Pregnancy with the 1^st transplant (%)

n = 82 (89.13) 85 deliveries (twins 3)

 Pregnancy with the 2^nd transplant (%)

n = 10 (10.87) 10 deliveries

 re-Tx once after that with pregnancy (%)

n = 11 (11.96)

 re-Tx twice after that with pregnancy (%)

n = 4 (4.35)

Additional extrarenal transplants:

 Combined pancreas-kidney-transplantation

n = 3^a

 Liver before kidney transplantation

n = 2

Timing of pregnancy after transplantation:

 Pregnancy in yr 1–5 after transplantation (%)

n = 44 (47.83)

 Pregnancy in yr 6–10 after transplantation (%)

n = 28 (30.43)

 Pregnancy in yr 11–20 after transplantation (%)

n = 17 (18.48)

 Pregnancy beyond yr 20 after transplantation (%)

n = 3 (3.26)

Number of pregnancies and deliveries per woman beyond the first trimester:

 1 Pregnancy (%)

n = 46 (50) 48 deliveries (twins 2)

 2 Pregnancies (%)

n = 18 (39.13) 37 deliveries (twins 1)

 3 Pregnancies (%)

n = 2 (6.52) 6 deliveries

 4 Pregnancies (%)

n = 1 (4.35) 4 deliveries

Immunosuppression during pregnancy

 Azathioprin, prednisolone (%)

n = 11 (11.96)

 Cyclosporine, prednisolone (%)

n = 40 (43.48)

 Cyclosporine, azathioprine, prednisolone (%)

n = 12 (13.04)

 Tacrolimus, prednisolone (%)

n = 11 (11.96)

 Tacrolimus, azathioprine, prednisolone (%)

n = 18 (19.57)

Mean pre-pregnancy eGFR:

 All pregnancies

59.39 ± 17.62 mL/min (n = 88)

 Pre-pregnancy eGFR ≥ 60 mL/min/1.73m²

73.91 ± 10.33 (n = 44)

 Pre-pregnancy eGFR ≥ 50-60 mL/min/1.73m²

54.16 ± 3.95 (n = 16)

 Pre-pregnancy eGFR ≥ 40-50 mL/min/1.73m²

45.79 ± 3.36 (n = 14)

 Pre-pregnancy eGFR < 40 mL/min/1.73m²

33.33 ± 4.29 (n = 14)

Fetal outcome:

 gestational age at birth (weeks)

34.44 ± 5.02 weeks (n = 88)

 live-birthrate

n = 86 (90.53%)

   < 37 SSW

n = 45 (von 76)

  < 34 SSW

n = 20 (von 76)

   < 28 SSW

n = 2 (von 76)

 Cesarian section (%)

n = 67 von 88 (76.1)

 Mean birth weight

2146.75 ± 926.14 (n = 82)

 Mean birth weight (only live birth)

2322.26 ± 781.98 (n = 79)

   ≤ 2500

n = 40 (of 79)

   ≤ 1500

n = 21 (of 79)

   ≤ 1000

n = 6 (of 79)