Constitutional growth delay, or CGD, is a term for a specific pattern of growth and development. It is not a disease or disorder but a normal, healthy variation in the timing of a child’s growth, commonly referred to as being a “late bloomer.” These children are healthy and grow at a normal rate for most of their childhood, but their overall tempo of physical maturation is slower than that of their peers. This results in a temporary period of short stature and a later start to puberty.
Identifying Constitutional Growth Delay
The diagnosis of constitutional growth delay is made by observing a distinct growth pattern over time and ruling out other medical conditions. Children with this growth pattern are born at a normal length and weight. However, their growth in height and weight slows down within the first few years of life, sometimes as early as three to six months of age. This deceleration can cause them to cross downward through percentiles on standard growth charts until about age two or three.
After this initial slowing, the child’s growth rate stabilizes and proceeds at a normal velocity, meaning they grow at the same speed as their peers. Their height will then track consistently along a lower percentile line on the growth chart throughout their prepubertal years. A corresponding delay in the start of puberty is also a main feature; boys may show no signs of puberty by age 14, and girls may show no signs by age 13.
A physician confirms the diagnosis through a combination of methods. This includes careful monitoring of growth measurements every six months to establish a clear trajectory on the growth curve. A thorough physical exam and a detailed family history are also taken, with specific questions about the growth patterns and pubertal timing of parents and other relatives. A central diagnostic tool is a bone age X-ray, usually of the left hand and wrist. This X-ray reveals that the child’s skeletal maturity is delayed compared to their chronological age, often by two years or more, confirming their body’s biological clock is running on a later schedule.
Underlying Causes
Constitutional growth delay is not the result of poor nutrition, chronic illness, or any deficiency in the child. Instead, it is understood to be an inherited trait passed down through families. The specific tempo of a child’s growth and the timing of their puberty are influenced by genetics, much like eye or hair color. A child with this growth pattern often has a parent, sibling, or other close relative who also experienced a “late bloomer” phase.
There is a strong hereditary link, with studies suggesting that between 60% and 90% of individuals with CGD have a family member with the same pattern. This family history might include a mother who started her menstrual periods later than average (e.g., age 14 or older) or a father who had a late growth spurt during his teenage years.
Prognosis and Management
The long-term outlook for children with constitutional growth delay is excellent. They are expected to progress through puberty, just on a later timeline than their peers. This delayed puberty allows for a longer period of childhood growth before the bones fuse, which ultimately enables them to reach a normal adult height that is appropriate for their family’s genetic potential.
The standard management approach is “watchful waiting,” which involves regular monitoring and reassurance without medical intervention. The primary challenge associated with the condition is often psychosocial, as being noticeably smaller than peers during adolescence can be a source of stress or anxiety for the child.
In some specific cases, particularly when a child is experiencing significant emotional distress, a doctor may discuss the option of a short course of hormone therapy. For boys, this might involve low-dose testosterone to help initiate pubertal development. It is important to understand that such treatment is not intended to increase the child’s final adult height. Its purpose is solely to help “jumpstart” puberty to lessen the social and psychological difficulties a child might be facing from the delay.