Table 2 Characteristics of fetal growth parameters during pregnancy
|  | First time (21–25 weeks, n = 14,609) | Second time (29-32 weeks, n = 13,944) | Third time (36-40 weeks, n = 11,300) |
|---|---|---|---|
Gestational age at measurements (weeks) | 23.3(0.68) | 29.9(0.8) | 37(0.72) |
AC | |||
 Original scale (cm) | 19.07(0.92) | 26.11(1.27) | 33.05(1.54) |
 Z-scores | -0.03(0.98) | -0.01(0.99) | -0.02(0.98) |
BPD | |||
 Original scale (cm) | 5.8(0.29) | 7.74(0.33) | 9.14(0.32) |
 Z-scores | -0.02(0.99) | 0(0.98) | -0.02(0.98) |
FL | |||
 Original scale (cm) | 4.13(0.19) | 5.65(0.23) | 6.86(0.22) |
 Z-scores | -0.02(0.99) | 0.01(0.99) | -0.01(0.98) |
HC | |||
 Original scale (cm) | 21.45(0.85) | 28.07(1) | 32.47(1.03) |
 Z-scores | -0.02(0.98) | 0(0.98) | -0.02(0.98) |
EFW | |||
 Original scale(g) | 614.6(67.92) | 1529.21(180.68) | 2935.97(304.27) |
 Z-scores | -0.14(0.99) | 0.01(0.99) | -0.03(0.97) |
 FGR (frequency) | 623(4.26) | 514(3.69) | 378(3.35) |