Growth and neurological outcome to 7 years of age were determined in 273 growth retarded infants, 341 infants from pregnancies complicated by subnormal urinary oestriol excretion and 72 control infants. By 1 year of age 80.6% of growth retarded infants were above the 10th percentile for weight. Growth continued so that after 2 years of age only 10.6% were beneath the 10th percentile. A neurological abnormality was detected in 9.5% of growth retarded infants and 8.3% of control infants (P = NS). Only 6 (2.2%) of the growth retarded infants were severely handicapped. A neurological abnormality was detected in 16.4% of infants from pregnancies with low oestriol excretion and although this incidence was higher than that of the control infants (8.3%), the difference failed to achieve statistical significance. The neurological abnormality was severe in only 7 infants (2.1%). The intelligence quotient (IQ) was the same in infants from pregnancies complicated by chronically low oestriol excretion whether hypertonic dextrose (mean IQ 103) had been administered to the mother or not (mean IQ 105). It is concluded that the pregnancy complicated by low oestriol excretion and/or fetal growth retardation should be treated with optimism.