Urocytogram, an index of maturity in premature infants

Cellular material found in urinary sediment stems essentially from exfoliated cells of the vesical triangle whose morphology is under the influence of the sex hormones. The study of cellular modifications forms the basis of a cytological procedure--the urocytogram. The urocytograms of 103 newborns, both premature and full term, made in the intensive care unit of the Department of Neonatal Medicine, Port-Royal Hospital, Paris, showed that marked changes in hormonal impregnation occur as a function of gestational age and permitted the establishment of a maturation index for the epithelium of the vesical triangle. In boys, the percentage of basal cells varied from 17.30 at 28 weeks' gestational age to 31.64 at term; while in girls the variation were less marked: 0.20 at 28 weeks to 1.37 at term. The oestrogen index (OI) was higher in a girl at 28 weeks (OI = 45.20) than in a girl born at term (OI = 13.50). The lower the gestational age the higher the pyknotic index (PI = 52.80 at 28 weeks), and the latter decreased as gestational age rose (PI = 23.12 at term). In boys, the oestrogen and pyknotic indices showed less variation (18.50 at 28 weeks and 15.29 at term). It thus appears that the urocytogram, a totally nontraumatic examination of urine samples obtained by simple miction, has its place among the tests of fetal maturity.