Fetal growth does not modify the relationship of infant weight gain with childhood adiposity and blood pressure in the Southampton women’s survey

Figures & data

Table 1. Fetal, infant, and maternal characteristics (n = 786).

			% missing
Fetal characteristics
Sex
Males	n (%)	395 (50.3)
Females	n (%)	391 (49.7)
EFW at 19-week scan (g)	Mean (SD)	310.3 (39.2)
Gestational age at 19-week scan (weeks)	Mean (SD)	19.5 (0.5)
EFW at 34-week scan (g)	Mean (SD)	2483.1 (291.3)
Gestational age at 34-week scan (weeks)	Mean (SD)	34.4 (0.5)
Infant characteristics
Birthweight (g): males	Mean (SD)	3531 (538)
Birthweight (g): females	Mean (SD)	3408 (558)
Gestational age at birth (weeks): males	Median (IQR)	40 (38.9,41.0)
Gestational age at birth (weeks): females	Median (IQR)	40 (39.2, 41.0)
Weight at 2-year visit (kg): males	Mean (SD)	12.9 (1.3)
Weight at 2-year visit (kg): females	Mean (SD)	12.3 (1.5)
Age at 2-year visit (years): males	Median (IQR)	2.0 (2.0, 2.1)
Age at 2-year visit (years): females	Median (IQR)	2.0 (2.0, 2.1)
Weight gain 0–2 years (kg): males	Median (IQR)	9.3 (8.6, 10.2)
Weight gain 0–2 years (kg): females	Median (IQR)	8.8 (8.0, 9.6)
Maternal characteristics
Age at recruitment (years)	Mean (SD)	28.4 (3.8)
Ethnicity (White)^a	n (%)	761 (96.8)
First trimester BMI (kg/m^2)	Median (IQR)	24.9 (22.7, 28.4)	22.4
Gestational diabetes (yes)	n (%)	8 (1.0)
Preeclampsia (yes)	n (%)	19 (2.4)
Multiparity (yes)	n (%)	367 (46.7)
Smoking in pregnancy (yes)^a	n (%)	70 (9.1)	1.7
Alcohol in 1st trimester (units per week)^a	Median (IQR)	0.3 (0, 1.5)	21.5
Educational level (≥university degree)^a	n (%)	210 (26.8)	0.3
Household Social class^a^b			1.7
(Professional or Management)	n (%)	513 (65.3)

^aBased on self-report.

^bAccording to Registrar General 1990 classification.

Table 2. Relationship of infant weight gain between ages 0–2 years with adiposity and blood pressure outcomes at age 6–7 years.

	BMI z-score		Percent body fat		Trunk fat (kg)		Systolic blood pressure (mmHg)		Diastolic blood pressure (mmHg)
	β	95% CI	β	95% CI	β	95% CI	β	95% CI	β	95% CI
Unadjusted
Infant weight gain (0–2 years)^a	0.50	0.44, 0.56	1.49	1.13, 1.85	0.41	0.35, 0.48	1.53	0.50, 2.56	0.54	−0.22, 1.31
Adjusted^b
Infant weight gain (0–2 years)^a	0.46	0.40, 0.52	1.32	0.96, 1.67	0.38	0.32, 0.44	1.53	0.49, 2.57	0.53	−0.23, 1.29

^aEstimates are presented per SD change.

^bAdjusted for maternal first-trimester BMI, smoking in pregnancy, social class, and gestational diabetes.

Figure 1. Estimated relationship of infant weight gain (0-2 years) with BMI z-score (6–7 years), across the distribution of mean fetal weight (19–34 weeks) and fetal weight change (19-34 weeks).

Table 3. Confounder-adjusted relationships of infant weight gain between ages 0–2 years with adiposity and blood pressure outcomes at age 6–7 years, testing for interactions with fetal weight variables.

	BMI z-score			Percent body fat			Trunk fat (kg)			Systolic blood pressure (mmHg)			Diastolic blood pressure (mmHg)
	β	95% CI	p(interaction)	β	95% CI	p(interaction)	β	95% CI	p(interaction)	β	95% CI	p(interaction)	β	95% CI	p(interaction)
Model 1^a
Infant weight gain  (0–2 years)^b	0.45	0.40, 0.51	–	1.31	0.96, 1.67	–	0.38	0.32, 0.44	–	1.50	0.45, 2.54	–	0.53	−0.24, 1.29	–
Mean fetal weight  (19–34 weeks)^b	0.12	0.06, 0.18	–	−0.02	−0.39, 0.36	–	0.01	−0.05, 0.08	–	−0.03	−1.19, 1.14	–	−0.19	−0.96, 0.58	–
Infant weight gain X  Mean fetal weight	−0.03	−0.09, 0.03	.39	−0.11	−0.48, 0.26	0.56	−0.04	−0.11, 0.03	0.29	−0.83	−1.80, 0.14	.09	−0.38	−1.10, 0.34	.30
Model 2^a
Infant weight gain  (0–2 years)^b	0.46	0.40, 0.51	–	1.31	0.96, 1.67	–	0.38	0.32, 0.44	–	1.50	0.46, 2,55	–	0.53	−0.23, 1.28	–
Change in fetal weight  (19–34 weeks)^b	0.13	0.07, 0.19	–	−0.01	−0.36, 0.38	–	0.02	−0.05, 0.09	–	−0.02	−1.16. 1.12	–	−0.17	−0.95, 0.61	–
Infant weight gain X  Foetal weight change	−0.02	−0.08, 0.04	.48	−0.06	−0.43, 0.31	0.75	−0.02	−0.09, 0.05	0.52	−0.91	−1.89, 0.07	.07	−0.38	−1.10, 0.33	.29

^aAdjusted for maternal first-trimester BMI, smoking in pregnancy, social class, and gestational diabetes.

^bEstimates are presented per SD change.

Figure 2. Estimated relationship of infant weight gain (0–2 years) with per cent body fat (6–7 years), across the distribution of mean fetal weight (19–34 weeks) and fetal weight change (19–34 weeks).

Figure 3. Estimated relationship of infant weight gain (0–2 years) with trunk fat (kg) (6–7 years), across the distribution of mean fetal weight (19–34 weeks) and fetal weight change (19–34 weeks).

Figure 4. Estimated relationship of infant weight gain (0–2 years) with systolic blood pressure (mmHg) (6–7 years), across the distribution of mean foetal weight (19–34 weeks) and foetal weight change (19-34 weeks).

Figure 5. Estimated relationship of infant weight gain (0–2 years) with diastolic blood pressure (mmHg) (6–7 years), across the distribution of mean foetal weight (19–34 weeks) and foetal weight change (19–34 weeks).