Adriëtte Oostvogels

12 Chapter 1 Adverse childhood cardiometabolic profile in offspring of women with overweight: the role of postnatal growth. Part 2 of this thesis focuses on how maternal overweight can affect childhood cardiometabolic profile in postnatal life, in particular through postnatal growth. Many studies have been performed on the influence of early growth on overweight/ obesity in childhood and adulthood. Maternal overweight may influence early growth both in utero and postnatal. In utero growth may be faster as a result of maternal overweight, which is reflected in heavier babies at birth. 8-13 Babies of mothers with overweight may also be born small for gestational age as a consequence of preeclampsia, 75 as their mothers are at increased risk of developing this disease. 24,25 These smaller babies often show rapid catch-up growth after birth. 76 Rapid postnatal growth, either as catch-up growth in small babies 76 or continuously faster growth in heavy babies, 77-80 may lead to higher rates of childhood obesity. 81-89 Irrespective of birth weight, postnatal growth may also be due to mothers with overweight having different infant feeding practices compared with normal weight mothers. 90-94 They are less likely to initiate 90-92 and continue 91-93 breastfeeding, and they tend to introduce solids at an earlier age. 93,94 Moreover, their breast milk composition differs from that of normal weight mothers, containing higher levels of inflamatory markers, “branched-chain” amino acids, and leptine, as well as a different composition of fatty acids. 95-98 All together, these factors might increase the rate of early postnatal growth. 99 Women with overweight are also more likely to have unhealthier nutrient intake, higher energy intake, and a more sedentary lifestyle. In this way, mothers with overweight may adversely influence the lifestyle and therefore the growth of their children as well, causing higher risks for childhood overweight. 100-102 The definition of growth differs between studies. Some studies define increased growth as higher BMI (z-scores) at a certain age, 82-84 while others define it as the BMI change between two time points. 86-89 In general children who develop overweight also have a higher BMI peak 88,89,103,104 and an earlier adiposity rebound compared with children with normal weight. 103,105 On the long-term, increased growth in infancy and/ or early childhood is associated with higher odds of adult overweight 106 and coronary events, 107 and with increased blood pressure 108,109 and insulin resistance. 110-113