Table 3.

Effect estimates of gestational age and selected miRNAs in relation to birthweight.

	Effect estimates of gestational age		Effect estimates of miRNA expression
miRNAs	Model 5a	Model 7c	Model 6b	Model 7c
let7g	78.7	78.9	−28.0	9.0
miR-1290	78.7	74.0	−121.1	−68.7
miR-138	78.7	77.1	−63.1	−50.0
miR-181a	78.7	78.1	−50.2	−46.1
miR-181c	78.7	77.8	−64.7	−57.5
miR-195	78.7	74.5	−98.3	−56.1
miR-199a	78.7	80.9	−35.3	−69.7
miR-27a	78.7	79.7	−8.9	27.9
miR-324-5p	78.7	78.6	32.6	1.1
miR-328	78.7	76.7	49.1	16.1
miR-424	78.7	79.7	7.8	−19.3
miR-489	78.7	77.1	−56.8	−43.0
miR-720	78.7	76.7	81.8	71.9

^a Model 5: $E\left[Birthweight\right]={\theta }_0+{\theta }_1\left(GestationalAge\right)+\theta {\mathrm{\prime }}_{2}Covariates$

^b Model 6: $E\left[Birthweight\right]={\beta }_0+{\beta }_1\left(miRNA\right)+\beta {\mathrm{\prime }}_{2}Covariates$

^c Model 7: $E\left[Birthweight\right]={\alpha }_0+{\alpha }_1\left(miRNA\right)+{\alpha }_2\left(GestationalAge\right)+\alpha {\mathrm{\prime }}_{4}Covariates$

Coefficients were scaled for a 1-SD change in miRNA expression in the placenta. Covariates included in the models were natural log cord blood arsenic exposure, maternal age, education, enrollment BMI, the number of past pregnancies, study site, infant sex and surrogate variables.