Evaluation of the prematurity risk on the ground of severity scores reflecting the action of different factors, maternal virus infection included.

A mathematical methodology is suggested which allows the a priori calculation of the risk of premature delivery, by a formula relying on the scores attributed to different specific risk factors (maternal virus infections included). The scores are estimated either directly, or starting from the scores of nonspecific factors. The statistical significance of the different scores, correlations and formulas is analyzed.