J Clin Endocrinol Metab. Published online January 2, 2007.
Clinical ContextLow birth
weight is a major cause of infant
morbidity and mortality, and SGA is associated with
increased risk for
health problems in later life, in particular coronary heart disease and
stroke. However, recommendations for the management of SGA have not
been standardized and controversy still exists about follow-up in
adulthood. In addition, the definition of SGA does not take into
account modifying factors such as maternal size, ethnicity, and parity.
This is a report from a consensus conference convened in February
2006 on recommendations for management of SGA consisting of 42 experts
in obstetrics, perinatal and neonatal medicine, pediatrics, pediatric
and adult endocrinology, epidemiology, and pharmacology. The group
examined a set of questions and reviewed, revised, and exchanged
documents. The group based the recommendations on available evidence
and expert opinion.
Study HighlightsThe definition of SGA requires accurate knowledge of gestational
age; measurements at birth of weight, length, and head circumference;
and a reliable cut-off from a relevant population.The cut-off has been set at variable standards (the 10th centile, 3rd centile, or at -2 SD or less than the mean
centile>), and the group recommends that SGA be defined as a weight or
length -2 SDs or less from the mean, and further subclassified for
weight, length, or both.Intrauterine growth retardation is a separate risk factor and such
babies, regardless of birth size, might require ongoing surveillance.Children born SGA tend to be 1 SD shorter than the mean and
experience accelerated growth in the first year resulting in stature
above -2 SD in 90%.A child born SGA should have length, weight, and head circumference
measured every 3 months in the first year, and every 6 months
thereafter.Those who remain short at 2 years should be identified and further treated.The preterm SGA infant can take 4 or more years to achieve a height in the normal range.SGA children have low lean mass and increased central obesity. Body
mass index is a limited method for defining body composition.Calorie-dense feeding for SGA infants might be inappropriate.Long-term exclusive breast-feeding past 24 weeks might prevent some of the intellectual impairment seen in SGA.Growth hormone can induce catch-up and head circumference growth in short SGA children, and IQ may improve.SGA children aged 2 to 4 years who show no evidence of catch-up
with a height -2.5 or less SD should be eligible for growth-hormone
treatment.Treatment should be considered in children older than 4 years who show no catch-up at a height -2 SD or less.The recommended growth-hormone dose range is 35 to 70 µg/kg per day.Discontinuation of growth-hormone treatment is recommended in adolescence when growth rate falls below 2 cm/year.In boys and girls born SGA, pubertal growth is modestly decreased,
but in girls menarche can occur 5 to 10 months earlier, resulting in
reduced adult stature.There might be an increased risk for ovarian dysfunction and reduced fertility in girls born SGA, but more data are needed.Bone age is a poor predictor of pubertal timing and adult height in
SGA children and is not recommended during routine follow-up.In boys born SGA, hyposapdias and cryptorchidism are more common.The prevalence of SGA in childhood obesity or the prevalence of obesity in SGA is not known.Insulin resistance might present early in SGA infants, especially
with rapid weight gain, leading to increased risk for abnormal glucose
metabolism.Treatment of obese SGA children should follow principles for the general population.A small effect size has been demonstrated for increased risk for
hypertension, obesity, and increased waist circumference in adults with
SGA.A 1-kg higher birth weight is associated with a 20% lower risk for coronary heart disease and stroke.High birth weight is associated with increased risk for cancer, best documented with breast cancer.There are insufficient data to justify specific surveillance of adults born SGA.There are no long-term surveillance data in adults treated with
growth hormone for short stature due to SGA, and it is prudent to
follow this group systematically.
Pearls for PracticeSGA children should be followed up during childhood and treated for inadequate growth and metabolic risks.Data for ongoing surveillance of adults born SGA are insufficient to support routine surveillance.
More abstracts about the New Guidelines Issued for Treatment of SGA children