l Introduction \ The etiology of prematurity exhibits many heterogenous factors and circumstances before and during pregnancy. Several authors developed Systems to assess the risk of a pre-term delivery. These scoring Systems have been become necessary, because up to 30 factors have been considered to have an influence on prematurity. The purpose has been always to select high risk patients who require intensive prenatal care in order to eliminate or to compensate such risk factors. In particular the significance of one single factor is often found to be very different from another one. Thus it has been essential to characterize each factor with a certain number of risk points. On the other hand the combüia-. tion of some circumstances may magnify or diminish the calculated risk, which a mere addition of points does not represent. PAPIERNIK reported 1969 [14] his coefficient for a risk of a premature delivery based on results of own studies and literature. In a recent report [15] he could show a decrease of prematurity rate (without twins) in the area of CLAMART from 10.1 % (1973) to 3.9% (1977), assumably due to efforts of recognization of pre-term risk, followed by adequate therapeutic measures. SALING published 1972 his prematurity-dysmaturity-prevention program (PDP-program) [20] which is based mainly on present and previous obstetrical characteristics; social factors are listed under variable factors. This useful and valuable program, and the resulting experiences with it [6] induced us to establish a special outpatient clinic for intensive prenatal care on the model of SALING's PDP-outpatient clinic. Our experiences have been reported in previous papers [9,16]. Although it was possible to lower the prematurity rate [16], this special outpatient clinic concentrates on high risk patients in our hospital, so that it will be doubtful whether a fürther decrease of pre-term deliveries in the hospital's statistics will be within reach. Also FEDRICK [4]