Fetal growth retardation is a universal problem. The growth-retarded fetus carries
a substantially increased perinatal mortality (1,2) and morbidity in the neonatal
period and during infancy (2,3).
The regulation of fetal growth is complex and still very poorly understood. It involves
genetic factors, maternal nutrition and cardiovascular adaptations, placental
growth and function, and to a lesser extent fetal factors, including fetal hormones.
The focus of this chapter is fetal energy and protein metabolism. As in postnatal
life, energy metabolism and protein metabolism are closely interrelated, based on
the contribution of net protein accretion to the energy cost of growth, and on the
contribution of protein oxidation, which is influenced by the supply and utilization
of nonprotein energy substrates, to the overall metabolic rate.
Although there are numerous problems with "intrauterine" growth curves, they
have probably done more to alert obstetricians and pediatricians to the complications
of aberrant intrauterine growth than any other single factor.
Intrauterine growth retardation (IUGR) is not itself a discrete disease process but
an abnormality of fetal growth common to a variety of different conditions (1-4).
Intrauterine growth retardation (IUGR) accounts for increased perinatal morbidity
and mortality, and the early identification of the growth-retarded fetus remains a key
factor in achieving the most favorable outcome for the infant and the mother.
"Management" of delivery means observing and taking stock of a great number
of factors concerning the mother and infant.
Nearly three decades ago it became apparent that a significant number of low
birthweight newborns classified as premature were born at term.
Low birthweight was originally defined as 2,500 g or below, but more recently it
has been revised to less than 2,500 g.
This paper describes a study coordinated by Professor Fernando Jose de Nobrega
and produced by a working team on undernutrition from the Brazilian Society of Pediatrics
In 1979, some 21 million low birthweight babies (<2,500 g) were born in the
world. This represents about 17% of all births in that year (1). In those countries
where the proportion of low birthweight is the highest and where action is needed,
data on birthweight are scarce or even non-existent.
The birthweight (BW) of a newborn infant is probably the most important single
factor that affects his/her survival and quality of life (1-8). Birthweight is determined
by two factors: the duration of gestation and the amount of intrauterine
growth; therefore birthweight can be modified by variation in combinations of these
Intrauterine growth retardation (IUGR) can result from a variety of environmental or genetic influences of fetal growth (1).
Dr. Rachagan: It has been reported in the British Journal of Obstetrics and Gynaecology that
oral correction of anemia in pregnancy is associated with a poor fetal outcome. Could Dr. Wharton
comment on this please?
There is general agreement among experts in human growth on the importance of
the intrauterine period and early childhood up to the age of 6 years as basic critical
stages in the development of man.
Adequate nutrition during pregnancy is a common goal of physicians and pregnant
Intrauterine growth retardation (IUGR) represents one of the most important perinatal
In the past, it was common practice to relate low birthweight to prematurity.
However, a number of environmental, maternal, placental, and fetal factors have
been recognized as causing intrauterine growth retardation (IUGR) in babies who
are small-for-gestational-age (SGA).