To explore the effect of maternal BMI class pre-pregnancy (overweight/obese v. healthy weight/underweight) on childhood diet quality and on childhood overweight/obesity risk.

Dietary data were collected using 3-d parental-completed food records for their children at ages 18 and 43 months. An index of diet quality was derived by classification of food items into core and non-core foods. Adjusted multiple linear regression analyses were used to explore the effect of maternal BMI class on diet quality in their children.

Avon, UK.

A 10% subsample of the Avon Longitudinal Study of Parents and Children. Nine-hundred and eighty children provided complete dietary data at 18 months and 769 at 43 months.

Children with overweight/obese mothers consumed greater amounts of energy from non-core foods than children with healthy weight/underweight mothers (0·20 MJ (48 kcal)/d more at 18 months (P < 0·001); 0·19 MJ (45 kcal)/d more at 43 months (P = 0·008)) in adjusted models. Diet quality deteriorated between 18 and 43 months (children reduced their dietary energy intake from core foods (P < 0·001) and increased intake from non-core foods (P < 0·001)). However, this change was not associated with maternal BMI class in adjusted models. Having an overweight/obese mother was associated with an increased odds of the child being overweight/obese at 43 months (OR 1·74 (1·17, 2·58)).

Children aged 18 and 43 months with overweight/obese mothers are likely to have a poorer quality diet than those with healthy/underweight mothers. Parents should be supported in discouraging the consumption of non-core foods in children at these ages.

To assess the association between pregestational BMI and offspring’s risk of overweight/obesity after accounting for the most important confounders, especially maternal smoking habit.

Prospective cohort study.

The Seguimiento Universidad de Navarra (SUN) study is a prospective cohort of Spanish graduates with more than 22 000 participants nationwide. Recruitment started in 1999, and it is permanently open. Data on diet, lifestyle and clinical diagnoses are collected at baseline and every 2 years.

Women from the SUN cohort who reported at least one pregnancy during follow-up (n 3496) were invited to this study. Among them, 1527 agreed to participate and completed an additional more detailed online questionnaire on their pregnancy history and their offspring’s nutritional status.

After excluding 165 children, we analysed data of 2791 participants born to 1485 mothers and observed that each 5 kg/m2 increase in pregestational BMI was associated with a 0·22 (95 % CI 0·15, 0·29) higher z-score in offspring’s BMI and higher risk of overweight/obesity (multivariable-adjusted relative risk (RR) 1·57 (95 % CI 1·39, 1·77)) in childhood or adolescence. Furthermore, we observed stronger association in children born to smoker mothers (RR 1·91; 95 % CI 1·48, 2·46) than from non-smoker mothers (RR 1·51; 95 % CI 1·31, 1·73) (Pfor interaction = 0·02).

We found a synergistic interaction between pregestational BMI and maternal smoking habit on offspring’s z-score of the BMI and in their risk of overweight/obesity. Although further research is needed to analyse dose–response relationships, these findings reinforce the importance of promoting healthy lifestyles in pregnant women in order to prevent childhood obesity.

To explore whether there is an association between socio-economic status and maternal BMI and duration of any breast-feeding/exclusive breast-feeding among Norwegian infants at 4 and 5 months of age in 2016.

Cross-sectional design. Baseline data from a randomized controlled trial. Data concerning breast-feeding were collected by FFQ.

Recruitment was done at child health-care centres and through Facebook in 2016. In total, 960 infants/parents registered for participating in the study Early Food for Future Health.

A total of 715 infant/mother dyads completed the questionnaire when the child was between 5 and 6 months old.

At 5 months of age, 81·0 % of infants were breast-fed and 16·4 % were exclusively breast-fed. Infants of highly educated mothers had higher odds of being breast-fed at 5 months compared with infants of mothers with less education. Infants of multiparous mothers had higher odds of being exclusively breast-fed for the first 5 months compared with infants of mothers with one child. Infants of mothers with overweight/obesity had reduced odds of both being breast-fed at all and being exclusively breast-fed at 4 months of age compared with infants of mothers with normal BMI.

Our results show that duration of breast-feeding varies with socio-economic status and maternal BMI in Norway. Targeting groups with low socio-economic status and mothers with overweight or obesity is important, as they are less likely to breast-feed according to recommendations.