Intrauterine growth rate in relation to anorectal and oesophageal anomalies.

a low birthweight. Many recent studies have drawn attention to the importance of intrauterine growth rate as judged by the difference between actual and expected weight at birth in relation to gestational age. The Perinatal Mortality Survey (Butler and Bonham, 1963) showed that 35% of babies who weighed less than 2500 g. at birth were born after the end of 37 weeks' gestation and thus were not premature. The infant who, when born, is small for the length of gestation, small-for-dates, may be small because of retardation of intrauterine growth, though Walker (1967) found that both the height of the mother and the sex of the baby may also affect the weight of the baby. However, the small-for-dates baby differs from the true premature infant in several ways, one being a higher incidence of congenital malformation (Van den Berg and Yerushalmy, 1966). Most reports of congenital anomalies in infants have recorded only the incidence of low birthweight, but have not distinguished between those who