Table 1.
Frequency distribution and maternal serum PFAS concentrations (in ng/mL) for select characteristicsa (n = 457).
| Frequency [n(%)] | PFOS Median (IQR) | PFOA Median (IQR) | PFHxS Median (IQR) | PFNA Median (IQR) | |
|---|---|---|---|---|---|
| Overall | 457 (100) | 13.8 (11.0, 17.7) | 3.0 (2.3, 3.8) | 1.9 (1.4, 2.5) | 0.4 (0.3, 0.5) |
| Birth weight (g) | 447 | ||||
| < 3290 | 148 (32.4) | 14.4 (12.0, 18.3)* | 3.2 (2.4, 3.8) | 1.9 (1.5, 2.4) | 0.4 (0.3, 0.5) |
| 3290–3720 | 142 (31.1) | 13.8 (11.5, 18.6)* | 2.9 (2.2, 3.8) | 1.8 (1.3, 2.5) | 0.4 (0.3, 0.4) |
| > 3720 | 157 (34.3) | 13.2 (10.1, 16.7)* | 2.8 (2.3, 3.7) | 1.9 (1.3, 2.3) | 0.3 (0.2, 0.4) |
| Crown to heel length (cm) | 412 | ||||
| < 50.3 | 137 (33.3) | 14.3 (11.2, 17.4) | 3.1 (2.3, 3.7) | 1.9 (1.4, 2.4) | 0.3 (0.3, 0.5) |
| 50.3–52 | 133 (32.3) | 14.0 (10.9, 19.5) | 3.0 (2.4, 4.2) | 1.9 (1.5, 2.5) | 0.4 (0.3, 0.5) |
| > 52 | 142 (34.5) | 13.6 (10.6, 16.5) | 2.9 (2.3, 3.6) | 1.8 (1.3, 2.2) | 0.3 (0.3, 0.4) |
| Head circumference (cm) | 416 | ||||
| < 34.5 | 137 (32.9) | 14.1 (11.5, 18.2) | 3.0 (2.3, 3.7) | 1.9 (1.5, 2.4) | 0.4 (0.3, 0.5) |
| 34.5–35.7 | 134 (32.2) | 14.4 (10.9, 18.0) | 2.9 (2.2, 3.7) | 1.7 (1.3, 2.5) | 0.4 (0.3, 0.4) |
| > 35.7 | 135 (32.5) | 13.4 (10.5, 16.7) | 2.9 (2.4, 3.8) | 1.9 (1.3, 2.3) | 0.3 (0.3, 0.5) |
| Maternal weight gain (kg) | 363 | ||||
| < 2.25 | 121 (33.3) | 13.8 (11.2, 17.1) | 3.0 (2.3, 3.8) | 1.8 (1.3, 2.4) | 0.6 (0.4, 0.9) |
| 2.25–5.40 | 122 (33.6) | 13.9 (10.7, 18.2) | 3.0 (2.2, 3.7) | 1.9 (1.5, 2.6) | 0.6 (0.4, 0.9) |
| > 5.40 | 120 (33.1) | 13.9 (10.3, 17.9) | 3.0 (2.3, 3.8) | 1.9 (1.4, 2.5) | 0.6 (0.4, 0.8) |
| Maternal age | 453 | ||||
| < 35 | 399 (88.1) | 13.9 (11.2, 17.7) | 3.0 (2.3, 3.7) | 1.8 (1.4, 2.4) | 0.4 (0.3, 0.5) |
| ≥35 | 54 (11.9) | 13.7 (10.6, 17.2) | 3.0 (2.2, 4.1) | 2.1 (1.3, 2.5) | 0.4 (0.3, 0.5) |
| Maternal BMI (kg/m3) | 429 | ||||
| < 18.5 | 8 (1.9) | 11.7 (9.4, 19.2) | 2.6 (1.5, 3.7) | 1.8 (1.1, 2.5) | 0.4 (0.2, 0.5) |
| 18.5–25 | 312 (72.7) | 14.1 (11.2, 18.3) | 3.1 (2.3, 3.8) | 1.9 (1.4, 2.5) | 0.4 (0.3, 0.5) |
| 25–30 | 82 (19.1) | 13.6 (11.3, 17.1) | 2.9 (2.3, 3.8) | 1.8 (1.4, 2.2) | 0.4 (0.3, 0.5) |
| > 30 | 27 (6.3) | 12.4 (10.9, 16.3) | 2.9 (2.6, 3.5) | 1.8 (1.3, 2.1) | 0.3 (0.3, 0.4) |
| Maternal educationb | 446 | ||||
| < O-level | 96 (21.5) | 13.9 (11.0, 17.3) | 2.8 (2.4, 3.6) | 1.9 (1.5, 2.3) | 0.4 (0.3, 0.5) |
| O-level | 154 (34.5) | 14.8 (11.9, 18.9) | 3.1 (2.3, 3.8) | 1.8 (1.3, 2.3) | 0.4 (0.3, 0.4) |
| > O-level | 196 (43.9) | 13.6 (10.7, 17.2) | 3.0 (2.3, 3.9) | 1.9 (1.4, 2.5) | 0.3 (0.3, 0.4) |
| Vitamin use | 436 | ||||
| Yes | 373 (85.6) | 14.0 (11.1, 17.9) | 3.0 (2.3, 3.8) | 1.8 (1.4, 2.4) | 0.4 (0.3, 0.5) |
| No | 63 (14.4) | 13.8 (10.1, 18.0) | 3.1 (2.2, 3.7) | 2.0 (1.5, 2.6) | 0.3 (0.2, 0.4) |
| Folic Acid Use | 436 | ||||
| Yes | 77 (17.7) | 14.1 (11.3, 18.0) | 3.1 (2.4, 3.8) | 1.9 (1.4, 2.5) | 0.4 (0.3, 0.5) |
| No | 359 (82.3) | 13.1 (10.0, 17.4) | 2.7 (2.1, 3.8) | 1.8 (1.3, 2.4) | 0.3 (0.2, 0.4) |
| Smoking during pregnancy | 442 | ||||
| No | 398 (90.0) | 14.0 (11.1, 17.9) | 3.0 (2.3, 3.8) | 1.9 (1.4, 2.4) | 0.4 (0.3, 0.5) |
| Yes | 44 (10.0) | 13.2 (11.0, 17.2) | 3.0 (2.4, 3.6) | 2.0 (1.7, 2.6) | 0.4 (0.3, 0.5) |
| Alcohol during pregnancy | 449 | ||||
| No | 385 (85.7) | 14.0 (11.2, 17.7) | 3.0 (2.3, 3.8) | 1.8 (1.4, 2.4) | 0.4 (0.3, 0.5) |
| Yes | 64 (14.3) | 12.6 (10.3, 16.7) | 2.7 (2.4, 3.5) | 2.0 (1.4, 2.6) | 0.4 (0.3, 0.4) |
| Parity | 446 | ||||
| 0 | 214 (48.0) | 14.3 (11.8, 18.0)* | 3.4 (2.7, 4.2)* | 2.0 (1.5, 2.6)* | 0.4 (0.3, 0.5)* |
| ≥1 | 232 (52.0) | 13.6 (10.6, 17.1)* | 2.6 (2.2, 3.4)* | 1.8 (1.3, 2.3)* | 0.3 (0.2, 0.4)* |
| Gestational age at sample (wk) | 457 | ||||
| ≤20 | 174 (38.1) | 14.6 (11.6, 18.6)* | 3.1 (2.4, 3.9)* | 2.0 (1.5, 2.6)* | 0.4 (0.3, 0.5)* |
| > 20 | 283 (61.9) | 13.6 (10.8, 16.9)* | 2.8 (2.2, 3.6)* | 1.8 (1.3, 2.4)* | 0.3 (0.3, 0.4)* |
Abbreviations: PFOS perfluorooctane sulfonic acid; PFOA perfluorooctanoic acid; PFHxS perfluorohexane sulfonic acid; PFNA perfluorononanoic acid; IQR interquartile range.
*
Indicates p < 0.05.
a
Compared using Kruskal-Wallis or Wilcoxon Rank Sum tests.
b
O-levels (ordinary levels) are required and completed at the age of 16.