Fig. 1

Protein and creatinine concentrations in 2212 urine samples from 1033 pregnant women. The oblique line differentiates the area of P/Cr > 0.27 (upper area) from P/Cr < 0.27 (lower area). In 2212 spot urine samples (1924 antenatal urine samples and 288 postnatal urine samples) from 1033 women, median [Cr] was 105 mg/dL and varied greatly, ranging from 8.1 to 831 mg/dL. Median [P] (range) was 17 (0.0–6170) mg/dL. There were 6 urine samples with [Cr] > 500 mg/dL. Five of the 6 urine samples (from 5 women) with [Cr] > 500 mg/dL were collected at GW 12.7 (8.7–20.3) and the other was at GW 31. The frequency of dilute urine samples with lower [Cr] was significantly higher among postnatal than antenatal urine samples: 4.9 % (14/288) vs. 2.1 % (40/1924), respectively (P = 0.012), for [Cr] < 20 mg/dL; and 9.4 % (27/288) vs. 3.8 % (73/1924), respectively (P = 0.0001), for [Cr] < 25 mg/dL