Table 3 Laboratory Reference Intervals by gestational age for phosphate, calcium, albumin-adjusted calcium, magnesium (mg/dL), and alkaline phosphatase (units/L)
Phosphate (mg/dL) | |||||
|---|---|---|---|---|---|
Gestational Age (weeks) | n | Mean | SD | Lower limit* | Upper Limit* |
23-27 | 51 | 6.5 | 0.9 | 4.9 | 8.2 |
28-31 | 119 | 6.3 | 1.0 | 4.3 | 8.2 |
32-34 | 191 | 6.1 | 0.8 | 4.6 | 7.8 |
35-36 | 119 | 6.1 | 1.0 | 4.2 | 8.0 |
> 36 weeks (term) | 52 | 5.7 | 0.7 | 4.3 | 7.1 |
Calcium (mg/dL) | |||||
23-27 | 51 | 10.0 | 1.0 | 8.1 | 11.9 |
28-31 | 115 | 10.2 | 1.2 | 8.0 | 12.5 |
32-34 | 176 | 10.5 | 1.0 | 8.6 | 12.4 |
35-36 | 110 | 10.4 | 1.1 | 8.3 | 12.5 |
> 36 weeks (term) | 52 | 10.9 | 0.5 | 9.8 | 11.9 |
Albumin-adjusted Calcium (mg/dL) | |||||
23-27 | 49 | 10.8 | 0.9 | 8.9 | 12.6 |
28-31 | 109 | 10.9 | 1.1 | 8.8 | 12.9 |
32-34 | 175 | 11.1 | 0.9 | 9.3 | 12.7 |
35-36 | 116 | 10.9 | 0.9 | 9.0 | 12.8 |
> 36 weeks (term) | 51 | 11.2 | 0.5 | 10.2 | 12.2 |
Magnesium (mg/dL) | |||||
23-27 | 48 | 1.9 | 0.2 | 1.6 | 2.3 |
28-31 | 127 | 1.9 | 0.3 | 1.4 | 2.4 |
32-34 | 193 | 1.8 | 0.2 | 1.5 | 2.2 |
35-36 | 120 | 1.8 | 0.2 | 1.4 | 2.3 |
> 36 weeks (term) | 53 | 1.9 | 0.2 | 1.5 | 2.2 |
Alkaline Phosphatase (units/L) | |||||
23-27 | 50 | 201 | 61 | 80 | 321 |
28-31 | 130 | 196 | 68 | 61 | 330 |
32-34 | 197 | 174 | 55 | 66 | 283 |
35-36 | 123 | 166 | 56 | 57 | 275 |
> 36 weeks (term) | 52 | 159 | 49 | 62 | 256 |