PURPOSE: to determine whether prenatal sonographic findings and uterine contractions can predict neonatal motor outcome in fetuses with open spina bifida. METHODS: we evaluated retrospectively 53 fetuses with open spina bifida from 1993 to 2001. These fetuses were born and followed-up at the fetal medicine units of the Hospital Sao Paulo ("Universidade Federal de Sao Paulo") and the "Hospital Santa Joana". The influence of the alterations observed through ultrasound scan on neonatal muscular strength (macrocrania, microcrania, level of the spinal column opening, clubfoot and type of fetus position) was evaluated. The influence of uterine contractions on neonatal motor outcome was also evaluated. All deliveries were made through cesarian section. c2 and Fisher tests were used for categorical comparisons. A p<0.05 was considered significant. RESULTS: Fifty-three cases of isolated open spina bifida were studied. Alterations of the cranial circumference size and the level of the lesion did not interfere in the neonatal motor perfomance. However, clubfoot and breech position showed to be predictors of an unfavorable neurological prognosis (p<0.05). Twenty-tree (43%) infants had clubfoot. Eighteen (78.3%) of these had abnormal leg movements. No infant in breech presentation (n=10) showed normal motor function. The presence of uterine contractions and the premature membrane rupture, observed in 13 fetuses (87%), were also linked to the alteration of neonatal muscular strength (p<0.05). CONCLUSION: clubfoot and breech presentation are ultrasonographic findings useful in predicting neurological neonatal outcome. Uterine contractions and premature membrane rupture are associated with poor motor neonatal outcome.