Table 3 Reference values for biochemical markers assessment in CKD and in pregnancy.

From: Nutrition care for chronic kidney disease during pregnancy: an updated review

 Women with CKDPregnancy without CKD
First trimesterSecond trimesterThird trimester
Bone mineral metabolism
Calcium (mg/dL)9–10.58.8–10.68.2–9.08.2–9.7
Phosphorus (mg/dL)3–4.53.1–4.62.5–4.62.8–4.6
Vitamin D
25 hydroxycholecalciferol (pg/mL)
30–6520–6572–16060–119
Parathyroid hormone (pg/mL)Stage 3: 35–70
Stage 4: 70–110
Stage 5 and dialysis: 150–300
10–1518–259–26
Alkaline phosphatase (IU/L)30–8517–8825–12638–229
Iron status
Hemoglobin (g/dL)11–12≥11.0≥10.5≥11.0
Hematocrit (%)37–47≥33≥32≥33
Serum iron (µg/dL)50–17072–14344–17830–193
Ferritin (ng/mL)Not dialysis >30
HD ≥ 20—PD > 100
6–1302–2300–116
Total iron binding capacity (TICB) (µg/dL)250–420278–403359–609
Transferrin saturation (%)a≥20Not reported18–929–98
  1. HD hemodialysis, PD peritoneal dialysis
  2. aMeasure when clinically stable, not measure in acute illness. Pregnancy references adapted from: Abbassi-Ghanavati, Greer, Cunningham. Pregnancy and Laboratory Studies. Obstet Gynecol. 2009;114:(6)1326–31. From refs. [36, 42]