Nine cases of fetal intrathoracic anomalies detected in utero and followed to birth are reviewed. There were 6 congenital diaphragmatic hernias (CDH), one congenital pleural effusion and two isolated cysts of the lung. All these conditions were potentially responsible for neonatal respiratory distress and received early intensive treatment after maternal transport and delivery had been arranged in a center with thoracic surgical facilities available. The risks of a delayed or missed diagnosis were thus avoided, especially for CDH. Despite intensive, traditional, respiratory support, started in the delivery room, mortality among prenatally detected cases of CDH was paradoxically high (83%), compared to mortality among 7 cases of CDH not detected in utero, referred in the same period to our Institution, and symptomatic within 6 h from birth (63%). With prenatal diagnosis the total number of CDH cases referred to a surgical center before birth increases. Many cases which would never have been treated in the past because of death before referral and treatment for severe pulmonary hypoplasia not compatible with life are thus observed and sometimes treated. Nevertheless, lung development continues to be a determining factor for survival even when intensive treatment at birth is available. Responsiveness to therapy is unpredictable before birth and proposed antenatal treatment is still far from being a realistic option. For the other three newborns, where a pleural effusion and pulmonary cysts were found, prenatal diagnosis helped to start appropriate treatment and to prevent neonatal hypoxia in two of them. In the third case, with an incommunicant, isolated pulmonary cyst, the outcome would have been favourable even without a prenatal diagnosis.