Effects of human amniotic fluid on fracture healing in rat tibia.
Fetal growth retardation is associated with abnormal umbilical flow velocity. We have begun a systematic study of growth factors and their relationship to this specific pattern of growth retardation. Using a specific double-antibody epidermal growth factor (EGF) 125I-radioimmunoassay, we studied urinary EGF in normal pregnancy from 5 to 42 weeks of gestation, and amniotic fluid EGF from 18 to 24 weeks. EGF levels increased from early pregnancy until 21-28 weeks, when they declined to a level at term similar to non-pregnant controls and first-trimester pregnancy levels. There was no significant difference in urinary EGF levels between women delivering appropriate-for-gestational-age (AGA) infants, and those delivering small-for-gestational-age infants (SGA). We conclude that the urinary EGF is not different in the SGA pregnancy from normal pregnancy.