[Fetal growth in prolonged pregnancy].

Posterm pregnancy still is a topic full of controversies in many aspects, such as diagnosis, perinatal risk and management. This paper suggests that a great number of fetuses from prolonged pregnancies, still grow after term, secondary to a persistent and adequate placental function; it's demonstrated, by comparing the distribution of newborn weights between term and posterm pregnancies. In the posterm group a significant increase in the incidence of hypertrophic newborns, is found. Dismature newborns, products of the placentary insufficiency in posterm pregnancy, although the point of interest of obstetricians, pediatricians and perinatologists because of its high rates of morbimortality, constitute a minority in comparison with fetus of posterm pregnancies with high newborn weights. It is possible that fetal hypertrophy by it self may be another cause of morbimortality in posterm pregnancies (because of dystocias, prolonged labor, altered fetopelvic relations, increased rates of cesarean sections, and others) that must be determined in future longterm, prospective analysis.