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Maternal BMI in the preconception period, and association with child zBMI growth rates
Arin C Deveci1,2, Charles D G Keown-Stoneman3,4, Jonathon L Maguire1,3,4,5,6,7
1Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto, Toronto, Canada.
Insights
Maternal preconception body mass index (BMI) impacts child growth rates and weight. Targeting the preconception period may help promote healthy child development and prevent obesity.
Area of Science:
- Pediatrics
- Public Health
- Obesity Research
Background:
- Elevated body mass index (BMI) and rapid early childhood growth predict obesity risk.
- The relationship between maternal preconception BMI and child growth is not well understood.
Purpose of the Study:
- To examine how maternal preconception BMI relates to child BMI z-score (zBMI) growth rates and mean zBMI.
- Focus on children aged 0-10 years.
Main Methods:
- Longitudinal cohort study of 499 children (TARGet Kids!).
- Maternal BMI measured preconception (2 years prior to pregnancy).
- Child weight and height tracked from birth to 10 years; analyzed with linear mixed models.
Main Results:
- Maternal preconception BMI correlated with child zBMI growth rates, especially in the first 4 months.
- A 5 kg/m² increase in maternal BMI linked to a 0.031 zBMI SD unit/mo higher growth rate (p=0.004).
- Higher maternal BMI also associated with 0.186 SD unit higher mean child zBMI (p=0.0002).
Conclusions:
- Maternal preconception BMI influences early childhood growth rates and mean zBMI.
- The preconception period is a potential window for interventions to foster healthy child growth and weight.
Background:
Elevated body mass index (BMI) and rapid growth in early childhood are important predictors of obesity risk. The association between maternal preconception BMI and child growth rates is unclear.
Objectives:
To assess the association between measured maternal preconception BMI and child age- and sex- standardized WHO BMI z-score (zBMI) growth rates and mean zBMI, in children aged 0-10 years old.
Methods:
A longitudinal cohort study was conducted with children (n = 499) enrolled in The Applied Research Group for Kids (TARGet Kids!) primary care practice-based research cohort. Maternal BMI was measured during the preconception period, defined as the 2 years prior to pregnancy. Repeated measures of child weight and height were obtained between 0 and 10 years of age. Linear mixed models were used to evaluate the association between maternal BMI and child zBMI growth rates and mean zBMI.
Results:
Maternal preconception BMI was associated with child zBMI growth rate during some growth periods, with the strongest association from age 0 to 4 months; a 5 kg/m2 higher maternal BMI was associated with 0.031 zBMI SD unit/mo higher growth rate (p = 0.004), and 0.186 SD unit higher mean child zBMI (p = 0.0002).
Conclusions:
Maternal preconception BMI was associated with growth rate and mean zBMI in early childhood. The preconception period may be an important target for health interventions to promote healthy child growth rate and weight outcomes.
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