Metric Pattern Cutting for Children's Wear and Babywear

The growth of children and adolescents

Designers of children's clothes should be aware of the way that a child's body shape changes as it grows and to recognise the shape of a child at a particular stage. Well-designed children's clothes take account of the child's continually changing shape.

In the first two editions of this book the size charts were constructed and divided in the way a child's body develops and changes. Today, clothes are designed and sold as ranges for particular target groups dictated by the large retailers. The revised size charts in the third, and this fourth edition, have been divided to enable pattern cutters to cut clothes for these ranges. However, by creating sub-divisions, the size charts still reflect the uneven body shape changes that occur during children's growth.

The problem of overweight and obese children has had to be considered when updating this edition. It is useful to understand how it may affect the size and shape of approximately 25% of children, and therefore the problem is discussed in ‘Overweight and Obese Children’. However, the following descriptions of the basic features of growth are relevant to the majority of children.

Basic features of growth

The rapid growth and changing shape of the child from birth to age one means that close increments in sizing have to be made; this is done usually in three-month intervals. It is at this stage that weight and the age of the child are the predominant descriptions for garment selection, whereas height becomes the critical sizing division once a child begins to walk.

The speed at which a child grows decreases steadily from shortly after birth onwards until puberty when the rate of growth accelerates (this acceleration is known as the ‘adolescent growth spurt’). Until this growth spurt occurs, there appears to be little difference between boys and girls in the speed at which they grow. There is a short-lived mid-growth spurt at about 7–8 years but this is often not detectable.

The decrease in the rate of growth varies from approximately 8cm per year at three years to 5cm per year at ten years. Manufacturers have decided to accept a 6cm height interval as a base for a coding scheme, as this approximates to the average growth per year over this period. However, it must be noted that the range of heights in children in any particular age group is larger than the amount of growth that occurs in any one year, therefore a child's age is only a very crude guide or ‘designation’ of his/her expected stature. It is better to link other body measurements to height rather than age, and one must recognise that age on clothing labels is only a secondary description. During puberty, age ceases to have even a descriptive value as variations in height linked to heredity are further distorted by the variability of the onset of puberty and the growth spurt.

In early childhood there is little difference between the sexes. Small differences begin to appear at four, but significant differences begin to appear at about seven. This means that it is advisable to offer a size chart for each sex from the age of four but necessary by seven. Puberty brings dramatic differences between boys and girls, the onset of puberty occurring eighteen months to two years earlier in the girl.

Children of the same height can have variable arm and leg measurements and these differences become more apparent as the limb length increases. Children in the North of England, Scotland and Northern Ireland have been found to be slightly smaller than average. This may be due in part to the greater numbers of working-class children in these areas. Significant differences can be found between children of classes I and II (managerial and professional occupations) and classes IV and V (semi-skilled and unskilled occupations). Children from classes I and II appear to be taller (2–5cm) but not necessarily heavier than classes IV and V.

Children from birth to age seven

The most apparent characteristic of a small child's shape is its head size: by the age of three the child's head has almost completed its growth. A small child has a head one fifth of its height, while the adult's head is only one eighth. The head size of a child must be taken into account when designing bodice openings for the head to pass through. From the age of two, the average child loses fat until about the age of eight. This ‘slimming down’ process is apparent and is generally spoken of as the child ‘losing his baby fat’.

Boys are often a little thinner than girls at this stage, but as the differences in measurements are small, a common size chart can be used. The most significant difference occurs on the hip/seat measurement and some manufacturers of boys’ wear take account of this.

Toddlers have very little waist shaping and their stance gives them a hollow back and protruding stomach. These features decrease as the child grows and loses fat.

Children from age seven to puberty

By the age of seven the posture of the child has straightened. From seven years to puberty the average child has a greater relative increase in body girth to height. Despite this increase, a girl's waist develops more shape. Girls who do little exercise, even if not overweight, will still retain abdominal fat and have less shape. At this period the legs of children of both sexes grow faster than the trunk.

Although the speed at which a boy and a girl grows is similar until puberty, the average girl is slightly shorter than the average boy and slightly heavier. During this period, figure differences become more apparent, the most significant being the wider shoulders of the boy and the smaller waist and larger hips of the girl (the latter features are increasingly apparent as the girl enters puberty earlier than the boy).

Boys and puberty

The average boy starts his growth spurt at about the age of thirteen and grows rapidly until the age of fifteen, then more slowly until he is seventeen. However, as the timing of the spurt varies, height and age have little correlation at this time. Age therefore has little relevance on size charts at this stage. Boys often become thinner during this growth spurt but they begin to gain muscle.

Before puberty, leg length grows faster than trunk length, but during the period of peak growth the trunk grows faster than the limbs, the rate of growth of the shoulders is at a maximum and the rate of growth of the head accelerates slightly. Boys have two more years of growth than girls and therefore attain a greater final height.

Girls and puberty

Girls begin to grow quickly at about the age of eleven or twelve; however, their growth spurt is shorter in duration than that of boys and proceeds at a slower rate. Because girls enter puberty earlier, a proportion of eleven to thirteen-year-old girls is taller than boys of the same age. Girls continue to get fatter during their growth spurt, but this is in the trunk rather than the limbs and a girl's hip size shows a particular increase.

The bust development of a girl is the most dramatic change in her shape. The early stages of development result in little bust prominence and it is only when the bust begins to develop a structural shape that a girl will require to have blocks which have bust darts. The age at which these different development stages of maturity are reached can differ widely; children between ten and fourteen of similar height and weight can have very different bust measurements. Girls with developing figures require a specific size chart and block construction as children's blocks are inadequate and women's blocks too mature. At this stage in a girl's development the relationship between height and age is now too variable to be recorded as yearly increments.

Overweight and obese children

Obesity and overweight is usually measured by BMI (body mass index, weight kg ÷ height m2). Although not a perfect measure, it is seen as the best single method of assessing these features over extensive populations. It was used by The Health Survey of England in 2002 which published some important statistics on children's weight and height from 1995–2002. The following findings would seem to be relevant to clothing producers.

Later studies appear to show that the trend towards overweight and obesity has continued from 2002. However, there is now a focus on this problem, and government health and education initiatives may begin to reduce this trend.

Exporters should note that the increased prevalence of childhood overweight and obesity is also occurring in most developed countries.

Waist circumferences

Some research into overweight and obesity focuses on the waist circumference. Sizing surveys developed for the clothing industry should use the same measuring position and method as that used in health studies, the measurement is taken ‘at the end of normal expiration’.

The sizing survey done for the BSI...