Table 5. Fully-adjusted estimated coefficients and 95% confidence interval for the association between covariates and size, tempo and velocity parameters on the GXXI data.

	GXXI (N  =  605) a
	Size			Tempo			Velocity
	%		95%CI	β b		95%CI	%	95%CI
Background c
Maternal height	0.5		0.2; 0.7	0.01		−0.01; 0.02	−0.05	−0.5; 0.4
Maternal age	−0.1		−0.4; 0.2	−0.01		−0.02; 0.01	0.6	0.01; 1.2
Maternal parity
Nulliparous	0		–	0		–	0	–
Parous	1.0		−2.2; 4.3	−0.17		−0.34; −0.01	−1.1	−7.4; 5.2
Maternal education d
Low	0		–	0		–	0	–
Medium	3.6		0.1; 7.2	0.003		−0.18; 0.19	−2.2	−9.2; 4.7
High	3.6		0.1; 7.1	0.08		−0.11; 0.26	−7.0	−13.9; −0.1
Intermediate e
Pre-pregnancy BMI
<18.5	−5.9		−12.3; 0.5	−0.09		−0.41; 0.23	2.6	−10.2; 15.4
18.5–24.99	0		–	0		–	0	–
25+	7.9		4.9; 10.8	0.26		0.11; 0.41	−4.9	−10.8; 0.9
Maternal smoking
No	0		–	0		–	0	–
≤1st trimester	−0.9		−6.4; 4.5	−0.02		−0.29; 0.25	6.2	−4.6; 16.9
>1st trimester	−2.8		−6.9; 1.3	−0.08		−0.28; 0.12	14.0	5.8; 22.2
	(N  =  492) f
Gestational diabetes	3.1	−3.9; 10.1			0.06	−0.13; 0.24	0.7	−12.7; 14.2
Gestational hypertension	−3.5	−12.2; 5.3			0.31	0.08; 0.53	8.7	−7.9; 25.3

^aModel fitted on the sample of data with no missing values for the following maternal variables: height, age, parity, educational level, pre-pregnancy BMI and smoking during pregnancy

^bModel is on the log-weight and age scales, thus the effect on tempo is on the age unit (months)

^cBackground variables are mutually adjusted and further adjusted for gender and gestational age

^dLow = ≤9 years, Medium = ≤12 years, High = Degree or higher

^eIntermediate variables are mutually adjusted and further adjusted for the background variables, gender and gestational age

^fModel fitted on the sample of data with no missing values for the following maternal variables: height, age, parity, educational level, and pre-pregnancy BMI; smoking during pregnancy, gestational diabetes and gestational hypertension