Maternal exposure to diluted diesel engine exhaust alters placental function and induces intergenerational effects in rabbits

Table 2 Fetoplacental biometry at 28 dpc for the first generation

Variable	Number of fetuses		Median [Q1; Q3]		Fully adjusted linear model
Variable	C	E	C	E	β value	CI	P-value
Fetal weight (g)	41	68	38.5 [36.0; 41.7]	34.45 [31.1; 37.8]	−1.895	[−5.362;1.571]	0.307
Crown-rump length (cm)	41	68	12.0 [11.6; 12.5]	11.7 [11.1; 12.1]	−0.107	[−0.494;0.28]	0.596
Biparietal diameter (mm)	41	66	17.9 [17.5; 18.2]	17.2 [16.3; 17.8]	−0.697	[−1.649;0.256]	0.178
Head length (mm)	41	66	29.5 [28.7; 30.2]	28.4 [27.4; 29]	−1.293	[−2.301;-0.2285]	0.029*
Abdominal perimeter (cm)	41	67	7.5 [7.3; 8.0]	7.2 [6.8; 7.5]	−0.529	[−1.058;0]	0.076
Brain weight (g)	40	68	0.92 [0.88; 0.96]	0.93 [0.86; 0.96]	0.011	[−0.055;0.077]	0.746
Brain/Fetus weight ratio	40	68	0.025 [0.023; 0.028]	0.027 [0.025; 0.030]	0.002	[−0.001;0.004]	0.241
Lung/Fetus weight ratio	39	66	0.029 [0.027; 0.031]	0.030 [0.028; 0.032]	0	[−0.001;0.002]	0.570
Heart/Fetus weight ratio	41	68	0.006 [0.005; 0.006]	0.005 [0.005; 0.006]	0	[0;0.001]	0.662
Liver/Fetus weight ratio	41	68	0.066 [0.063; 0.072]	0.068 [0.062; 0.071]	−0.002	[−0.007;0.003]	0.514
Kidney/Fetus weight ratio	39	64	0.0006 [0.0006; 0.0007]	0.0006 [0.0005; 0.0007]	0	[0;0]	0.999
Placental weight (g)	41	68	7.32 [6.64; 8.43]	7.51 [6.83; 8.57]	0.153	[−0.794;1.1]	0.756
Labyrinthine area weight (g)	41	66	5.03 [4.41; 5.92]	4.99 [4.34; 6.05]	−0.17	[−1.003;0.663]	0.695
Decidual weight (g)	41	66	2.16 [1.98; 2.56]	2.51 [2.14; 2.96]	0.307	[−0.164;0.778]	0.226
Placental efficiency	41	68	5.29 [4.65; 5.51]	4.64 [3.92; 5.00]	−0.63	[−1.187;-0.074]	0.049*

Female rabbits inhaled 1 mg/m³ of NP, 2 h/day, 5 days/week, from 3 dpc to 27 dpc. Dams were euthanized and fetoplacental units of control (C) and exposed (E) group were collected at 28 dpc. Effect of pregnancy exposure to engine diesel exhaust on first-generation fetuses was estimated using a linear model with random effect of dam adjusted for litter size and position of the fetus in the horn. All data are expressed as median [Q1; Q3] (*p < 0.05, compared with control group)