TABLE 1

All mothers (n=13 113)	n	Overweight (weighted %)	Univariate OR (95% CI)
Potential confounding factors
Maternal ethnic group
White	11 253	23.3	1
Mixed	111	26.6	1.19 (0.76, 1.87)
Indian	347	11.9	0.44 (0.31, 0.63)
Pakistani or Bangladeshi	784	19.1	0.78 (0.66, 0.92)
Black Caribbean or Black African	389	30.2	1.42 (1.09, 1.87)
Other ethnic group	209	21.7	0.92 (0.58, 1.45)
Maternal socioeconomic circumstances
Managerial and professional occupations	3754	23.2	0.94 (0.83, 1.06)
Small employers and own account workers	470	19.3	0.75 (0.58, 0.96)
Intermediate occupations	2290	21.3	0.84 (0.73, 0.97)
Lower supervisory and technical occupations	720	23.1	0.94 (0.76, 1.16)
Semi-routine and routine occupations	4598	24.3	1
Never worked and long-term unemployed	1141	22.6	0.91 (0.75, 1.10)
Household income
£0–11 000 per annum	3040	23.9	1
£11 000–22 000 per annum	3845	24.0	1.00 (0.88, 1.14)
£22 000–33 000 per annum	2777	23.8	0.99 (0.87, 1.14)
£33 000+ per annum	3152	21.1	0.85 (0.73, 0.99)
Highest academic qualification
GCSE grades A–C or higher	9548	22.3	1
GCSE grades D–G or lower	3553	25.1	1.17 (1.04, 1.31)
Age at first live birth, per 5-year increase	12 751		0.96 (0.92, 1.00)
Age at MCS birth, per 5-year increase	13 104		1.00 (0.96, 1.04)
Lone motherhood status
Non-lone mother	11 147	22.6	1
Lone mother	1966	26.1	1.21 (1.06, 1.39)
Number of children in the household
1	3269	22.7	1
2 or 3	8488	23.0	1.02 (0.91, 1.14)
4 or more	1356	24.5	1.10 (0.93, 1.30)
Maternal pre-pregnancy body size
Normal weight	8718	19.7	1
Overweight	3634	31.1	1.84 (1.66, 2.03)
Smoked during pregnancy
No	8573	22.2	1
Yes	4494	24.5	1.14 (1.03, 1.25)
Birthweight (kg)	13 093		1.83 (1.66, 2.01)
Potential mediating factors
Breastfeeding duration
4 months	3436	20.4	1
Never breastfed	4178	25.5	1.34 (1.18, 1.52)
<4 months	5491	23.2	1.18 (1.05, 1.33)
Introduction of solid food
4 months	8501	21.6	1
<4 months	4609	25.7	1.26 (1.14, 1.38)
Television viewing daily
Less than 1 h	3046	21.1	1
1–2 h	7724	23.4	1.14 (1.03, 1.28)
More than 3 h	2342	24.8	1.23 (1.06, 1.44)
Whether child has meals at regular times
Always	6240	22.7	1
Usually	5651	23.6	1.05 (0.96, 1.16)
Sometimes or never	1221	22.2	0.97 (0.82, 1.15)
Who primarily cooks the main meal
Main respondent	6856	22.6	1
Partner	822	21.3	0.93 (0.76, 1.13)
Both share responsibility	2154	24.6	1.12 (0.99, 1.26)
Mothers in employment (n=7629)
Type of day care
Main/partner	1738	22.9	1
Informal	2972	25.4	1.15 (0.99, 1.33)
Formal	2272	22.5	0.98 (0.84, 1.14)
Working atypical hours weekly—first contact
No	3617	24.1	1
Yes	2512	23.7	0.98 (0.85, 1.13)
Working atypical hours weekly—second contact
No	3915	23.7	1
Yes	2868	23.1	0.97 (0.85, 1.10)
Do not spend enough time with child because of work
No	7122	23.2	1
Yes	498	28.6	1.33 (1.06, 1.65)

 Abbreviations: CI, confidence interval; MCS, Millennium Cohort Study; OR, odds ratio.

 Missing number of cases for all mothers: maternal ethnic group (20), socioeconomic circumstances (140), household income (299), highest academic qualification (12), age at first live birth (362), age at MCS birth (9), main pre-pregnancy body size (761), smoked during pregnancy (46), birthweight (20), breastfeeding duration (8), introduction of solid food (3), television viewing (1), whether child has meals at regular times (1) and who primarily cooks the main meal (3281).

 Missing number of cases for mothers in employment: type of day care (647), working atypical hours weekly—first contact (1500), working atypical hours weekly—second contact (846) and do not spend enough time with child because of work (9).