Background
Methods
Database development
Data retrieval
Data processing
Sample size estimation
Primary outcome
Statistical analysis
Results
Characteristics | Non-SGA Group | SGA Group | P-value* |
---|---|---|---|
Maternal age (yr) + SD | 28.3 + 11.2 | 28.8 + 6.3 | 0.464 |
Maternal weight (Kg) + SD | 57.5 + 11.3 | 53.9 + 11.2 | < 0.001 |
Gestational week at sampling +SD | 15.5 + 2.0 | 15.5 + 2.9 | 0.824 |
Gestational week at delivery +SD | 38.4 + 1.7 | 37.4 + 2.8 | < 0.001 |
Birth weight (gm) + SD | 3068 + 444 | 2162 + 418 | < 0.001 |
Parity | 0.129 | ||
•Nulliparous | 48.7% | 51.9% | |
•Parous | 51.3% | 48.1% |
Biomarkers | The models |
---|---|
AFP levels | ln (AFP level) = 1.536 + 0.0161 (GA: week) - 0.0054 (Weight: Kg) - 0.0293 (DM); (r = 0.368; p-value < 0.001) |
b-hCG levels | ln (b-hCG level) = 1.875–0.0164 (GA: week) - 0.0052 (Weight: Kg) + 0.0006 (Age, year) - 0.0487 (DM); (r = 0.392; p-value < 0.001) |
uE3 levels | ln (uE3 level) = 0.2610 + 0.0236 (GA: week) - 0.0013 (Weight: Kg) – 0.0345 (DM) - 0.0005 (Age, year); (r = 0.274; p-value < 0.001) |
IHA levels | ln (IHA level) = 2.6962–0.0068 (GA: week) - 0.0032 (Weight: Kg) + 0.0007 (Age, year)- 0.1383(DM); (r = 0.398; p-value < 0.001) |
Group | Non-SGA Group | SGA Group | P-value |
---|---|---|---|
Means + SDa | |||
AFP MoMs | 1.077 + 0.736 | 1.417 + 0.706 | < 0.001 |
b-hCG MoMs | 1.192 + 4.306 | 1.288 + 0.761 | 0.590 |
uE3 MoMs | 1.105 + 0.998 | 0.965 + 0.418 | 0.001 |
IHA MoMs | 1.046 + 0.443 | 1.299 + 0.900 | < 0.001 |
Median (IQR)b | |||
AFP MoMs | 0.969 (0.48) | 1.288 (0.57) | < 0.001 |
b-hCG MoMs | 0.928 (0.35) | 1.087 (0.46) | < 0.001 |
uE3 MoMs | 1.020 (0.53) | 0.877 (0.34) | < 0.001 |
IHA MoMs | 0.957 (0.32) | 1.129 (0.45) | < 0.001 |
Group | Non-SGA Group (n: 9577) | SGA Group (n: 578) | P-value | Relative risk (95%CI) |
---|---|---|---|---|
AFP > 2 MoMs | 355 (85.1%) | 62 (14.9%) | < 0.001 | 2.81 (2.20–3.58) |
AFP < 2 MoMs | 9222 (94.7%) | 516 (5.3%) | ||
b-hCG > 2 MoMs | 321 (85.4%) | 55 (14.6%) | < 0.001 | 2.74 (2.11–3.54) |
b-hCG < 2 MoMs | 9256 (94.7%) | 523 (5.3%) | ||
uE3 < 0.5 MoMs | 316 (90.8%) | 32 (9.2%) | 0.004 | 1.65 (1.17–2.32) |
uE3 > 0.5 MoMs | 9261 (94.4%) | 546 (5.6%) | ||
IHA > 2 MoMs | 253 (88.5%) | 33 (11.5%) | < 0.001 | 2.09 (1.50–2.91) |
IHA < 2 MoMs | 9324 (94.5%) | 545 (5.5%) |
Biomarkers | The models predicting small-for-gestational age (probability) |
---|---|
AFP MoMs | ln (Odds ratio) = −3.1403 + 0.2863 (AFP MoM) |
b-hCG MoMs | ln (Odds ratio) = −2.8127 - 0.0042 (b-hCG MoM) |
uE3 MoMs | ln (Odds ratio) = − 2.0289 - 0.7609 (uE3 MoM) |
IHA MoMs | ln (Odds ratio) = − 3.4347 - 0.5558 (b-hCG MoM) |
Combined biomarkers | ln (Odds ratio) = −4.4908 + 1.6877 (AFP MoM) + 0.8965 (IHA MoM) - 0.3248 (AFP MoM x IHA MoM) - 0.6725 (AFP MoM x uE3 MoM) |