1785 newborns of 37 weeks GA or more, were studied during a 15 months period at the Port-Royal Maternity Hospital. This study suggests that cerebral abnormalities during the neonatal period in fullterm neonates are related to deleterious intra partum factors. In 57 newborns, clear cut signs of cerebral birth injury were observed, in 31 newborns only mild and transitory signs were observed. These 88 newborns were compared with 1655 having had a normal neurological examination within the first week of life. We focused particulary on dysfunctional labor patterns, specifically false labor, protracted active phase dilatation, protracted descent or a marked caput succedaneum. When these abnormal patterns are followed by oxytocin infusion and forceps extraction, primiparity appears linked with a high risk of cerebral birth injury. Within cephalic presentations, the occipito-posterior position is carrying the same high risk. The most severe degree of cerebral birth injury has nearly disappeared. However, the main problem of modern obstetrics is one of eradicating brain damage of moderate degree without reaching an excessive incidence of C. section.