Table 3.
Creatinine in pregnancy as a percentage of nonpregnant value according to trimester
| Trimester | First | Second | Third |
|---|---|---|---|
| Number of included studies | 19a | 22 | 30 |
| Number of creatinine measures in pregnancy | 816a | 1183 | 2422 |
| Mean creatinine in pregnancy as % of nonpregnant mean value (95% CI) | 84% (76–90) | 77% (72–83) | 80% (77–84) |
| Example mean creatinineb | 56 μmol/l (0.63 mg/dl) | 52 μmol/l (0.59 mg/dl) | 54 μmol/l (0.61 mg/dl) |
| Upper limit creatinine as % of nonpregnant upper limit based on a 95% reference range (95% CI) |
85% (76–93) | 80% (73–89) | 86% (83–89) |
| Example upper limit creatinineb | 76 μmol/l (0.86 mg/dl) | 72 μmol/l (0.81 mg/dl) | 77 μmol/l (0.87 mg/dl) |
CI, confidence interval.
a
Nineteen studies (816 creatinine measures) inform the mean value and 18 studies (628 creatinine measures) inform the upper limit.
b
Example creatinine values are based on a typical value for nonpregnant women of 67.5 μmol/l (0.76 mg/dl), and an upper limit of 90 μmol/l (1.02 mg/dl).12