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* Address for correspondence: T. Norris, Centre for Global Health and Human Development, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK. (Email [email protected])
Introduction
It is widely accepted that risks for non-communicable diseases in adulthood are determined not only by concurrent lifestyle factors, such as diet and levels of physical activity, but also by exposures encountered in early life, either pre- or postnatally [an area of research called Developmental Origins of Health and Disease (DOHaD)].
The most widely researched associations within the DOHaD paradigm have been between birth weight and indicators of cardiovascular and metabolic health in later life. 1–9 Birth weight is an easily accessible proxy for ‘the overall maternal, environmental and placental factors that influence the efficiency of nutrient transfer to the fetus, and thus overall fetal growth’. 10 Nevertheless, birth weight is unable to provide insight into growth patterns during different stages in utero and offers little information about critical periods of development in the prenatal period.
Early postnatal life is also a period of substantial developmental plasticity in which the infant seeks to regain, through catch-up growth, its position in its programmed growth canal. Canalisation is the phenomenon in which an individual, when in an environment that does not constrain growth, displays a growth pattern that tracks along a given centile position. 11 Using birth weight as a proxy for the entire prenatal period, however, means that any discussion regarding the beginnings of canalisation is limited to the postnatal period only. Identification of where or when the fetus was potentially canalised is impossible and thus one is also unable to determine whether the amount of catch-up growth exhibited in infancy is appropriate or whether it represents rapid growth leading to an elevation of risk. If the canalised growth curve can be identified in utero a more accurate distinction between healthy catch-up growth and deleterious rapid growth can be made.
Routine ultrasound examination during pregnancy is now a standard part of antenatal provision across much of the developed world. Gravidas typically present for two to three scans over the course of pregnancy, in which repeated measurements of various fetal biometric dimensions [abdominal circumference (AC), head circumference (HC), femur length (FL), bi-parietal diameter (BPD), estimated fetal...