Table 1 Characteristics of the study sample from the NICHD fetal Growth Studies–Singletons (n = 260)
|  | Mean ± SD or N (%) or Median [p25-p75] | |
|---|---|---|
Maternal age, years | 27.6 ± 5.2 | |
Gestational age at enrollment, weeks | 12.7 ± 0.9 | |
Maternal pre-pregnancy BMI, kg/m2 | 23.3 ± 2.9 | |
Maternal race/ethnicity | ||
 Non-Hispanic White | 67 (25.8) | |
 Non-Hispanic Black | 59 (22.7) | |
 Hispanic | 86 (33.1) | |
 Asians | 48 (18.5) | |
Parity | ||
 Nulliparous | 126 (48.5) | |
 Parous | 134 (51.5) | |
Infant sex | ||
 Male | 130 (50.0) | |
 Female | 130 (50.0) | |
Maternal POP plasma concentration | ||
Chemical class | Chemicals | Â |
  OCPs (ng/g) |   HCB | 6.28 [3.50, 10.10] |
|  |   Trans-nonachlor | 4.25 [2.48, 7.35] |
|  | p,p′-DDE | 85.26 [54.09, 218.81] |
|  |   Σ OCPs | 98.83 [65.70, 228.20] |
  PBDEs (ng/g) |   PBDE 47 | 8.64 [3.60, 16.67] |
  PCBs (ng/g) |   PCB 138/158 | 5.03 [2.78, 8.17] |
|  |   PCB 153 | 5.74 [3.18, 10.09] |
|  |   PCB 180 | 3.30 [1.90, 5.25] |
|  |   Σ PCBs | 14.13 [8.06, 23.24] |
  PFASs (ng/mL) |   PFDA | 0.24 [0.16, 0.42] |
|  |   PFHxS | 0.70 [0.43, 1.27] |
|  |   PFNA | 0.75 [0.54, 1.22] |
|  |   PFOA | 2.20 [1.30, 3.07] |
|  |   PFOS | 4.74 [3.20, 7.65] |
|  |   PFUnDA | 0.16 [0.09, 0.32] |
|  |   Σ PFASs | 9.33 [6.39, 14.09] |