Table 1 Characteristics of the study population, PM2.5 exposure and placenta cell types
|  | All (N = 226) | Female (N = 101) | Male (N = 125) | P-value |
|---|---|---|---|---|
Gestational age (wks.), mean (SD) | 38.96 (1.50) | 39.04 (1.50) | 38.90 (1.50) | 0.32 |
Maternal race/ethnicity, N (%) | ||||
White | 72 (31.86%) | 30 (29.70%) | 42 (33.60%) | 0.59 |
Black | 91 (40.27%) | 38 (37.62%) | 53 (42.40%) | 0.47 |
Hispanic | 46 (20.35%) | 25 (24.75%) | 21 (16.80%) | 0.47 |
Other | 14 (6.19%) | 8 (7.92%) | 6 (4.80%) | 0.54 |
Maternal education, N (%) | ||||
High school or less, N (%) | 61 (26.99%) | 33 (32.67%) | 28 (22.40%) | 0.09 |
Maternal age at birth, mean (SD) | 30.57 (5.59) | 30.68 (5.87) | 30.48 (5.38) | 0.59 |
Pregnancy complications, N (%) | ||||
Preeclampsia | 15 (6.36%) | 5 (4.95%) | 10 (8%) | 0.63 |
Eclampsia | 2 (0.88%) | 0 (0.00%) | 2 (1.60%) | 1.00 |
Season of birth, N (%) | ||||
Spring (March to May) | 59 (26.11%) | 25 (24.75%) | 34 (27.20%) | 0.87 |
Summer (June – August) | 54 (23.89%) | 26 (25.74%) | 28 (22.40%) | 0.91 |
Fall (September – November) | 52 (23.01%) | 24 (23.76%) | 28 (22.40%) | 0.93 |
Winter (December – February) | 61 (26.99%) | 26 (25.74%) | 35 (28%) | 0.98 |
PM2.5 exposures, mean (SD) | ||||
Pregnancy | 8.33 (0.97) | 8.42 (0.99) | 8.25 (0.95) | 0.19 |
First trimester | 8.25 (1.36) | 8.40 (1.45) | 8.12 (1.28) | 0.14 |
Second trimester | 8.24 (1.34) | 8.28 (1.43) | 8.20 (1.26) | 0.65 |
Third trimester | 8.56 (1.77) | 8.66 (1.69) | 8.47 (1.83) | 0.42 |
Cell-type proportions, mean (SD) | ||||
Syncytiotrophoblast | 0.636 (0.069) | 0.623 (0.074) | 0.644 (0.064) | 0.023 |
Trophoblasts | 0.091 (0.049) | 0.099 (0.052) | 0.084 (0.046) | 0.020 |
Stromal | 0.127 (0.026) | 0.129 (0.026) | 0.125 (0.026) | 0.244 |
Endothelial | 0.099 (0.027) | 0.102 (0.025) | 0.096 (0.028) | 0.072 |
Hofbauer | 0.012 (0.011) | 0.010 (0.009) | 0.014 (0.011) | 0.003 |
nRBC | 0.036 (0.010) | 0.036 (0.009) | 0.036 (0.010) | 0.753 |