Table 6.
Associations between pathway-specific placental gene expression and maternal urinary phthalate metabolites, using a quintile model approach.
| β-Coefficient (SE), p-value |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Steroidogenesis: CYP19, 17β-HSD, P450scc, CYP1B1a |
Trophoblast differentiation: PPAR γ, AhR, HCGb |
|||||||||
| Phthalate metabolite | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | p-Valuec | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | p-Valuec |
| MEHP | 0.26 (0.35) | −0.28 (0.47) | −0.13 (0.43) | 0.30 (0.42) | 0.29 | 0.02 (0.29) | −0.15 (0.26) | −0.58 (0.30) | −0.43 (0.26) | 0.22 |
| MEOHP | −0.50 (0.38) | −0.34 (0.28) | −0.95 (0.43)* | −0.03 (0.39) | 0.06 | −0.59 (0.31) | −0.18 (0.24) | −0.92 (0.25)** | −0.83 (0.23)** | 0.002 |
| ∑DEHP metabolitesd | −0.36 (0.36) | 0.03 (0.42) | −0.40 (0.41) | −0.01 (0.47) | 0.54 | −0.13 (0.30) | −0.90 (0.33)* | −0.90 (0.28)** | −0.92 (0.27)** | 0.02 |
| MnBP | 0.72 (0.39) | 0.48 (0.46) | 0.83 (0.38)* | −0.61 (0.41) | 0.001 | 0.07 (0.29) | −0.52 (0.26)* | 0.33 (0.28) | 0.57 (0.21)** | 0.004 |
| MiBP | 0.14 (0.53) | 0.35 (0.61) | −0.18 (0.45) | −0.22 (0.44) | 0.71 | 0.43 (0.24) | 0.19 (0.36) | −0.92 (0.20)** | −0.44 (0.23) | 0.0002 |
| MBzP | 0.14 (0.49) | 0.09 (0.42) | −0.14 (0.43) | 0.12 (0.35) | 0.89 | 0.04 (0.30) | −0.52 (0.27) | −0.67 (0.24)** | −0.42 (0.26) | 0.01 |
a
n = 54, adjusted for gene, qPCR batch (CYP1B1), year of delivery, season of delivery, and level of education.
b
n = 54, adjusted for gene, qPCR batch (AhR, PPARγ), season of delivery, level of education, net weight gain, mother’s ethnicity, and history of hypertension.
c
The type 3 test of fixed effects, a four degrees of freedom test of whether there is any difference among the 5 groups. Quintile 1 is the referent group.
d
The square root of specific gravity was included as an independent term in the model.
*
p = 0.05,
**
p = 0.01; quintile 1 is the referent group in the regression models.