[Congenital diaphragmatic hernia: antenatal care].

The prenatal evaluation of the postnatal prognosis of fetuses displaying congenital diaphragmatic hernia (CDH) has improved over the past five years. Although the accuracy of these outcome predictions remains a matter of debate, it seems important that all teams in charge of those fetuses use the same prognostic factors in order to be able to improve and compare their practice. Prediction will be based on Lung over Head Ratio (LHR) between 22 and 28 weeks or the LHR observed/expected whatever the gestational age, (the measurement of which relies on very strict criteria), the position of the liver and lung volumes measured by MRI. These factors allow the identification of a group of fetuses likely to have a poor outcome. In the group with LHR less than 1 or LHR o/e less than 25% and where the liver is in the thorax, survival is less than 20%. In utero treatment could be offered to these fetuses. A balloon can be placed in the trachea, under the vocal cords, by foetoscopy between 28 and 30 weeks of pregnancy. The balloon is retrieved at 34 weeks. The preliminary results show that survival in this group increases from 20% to up to 50%. The morbidity does not seem to be increased but is currently under evaluation.