Inclusion Criteria:  Patients aged 18 years or more, who are able to consent, and affiliated to social security Singleton pregnancy with fetus with isolated left-sided congenital diaphragmatic hernia (no additional malformation nor chromosomal abnormality) and:  Severe pulmonary hypoplasia defined as observed on expected 'lung-to-head ration' (O/E LHR) <25% irrespective of the liver position as measured between 27wks and 29wks + 6 days Or Moderate pulmonary hypoplasia defined as O/E LHR 25-34.9% (liver up or down) or O/E LHR 35-44.9% with liver up as measured between 30wks and 31wks + 6 days  Exclusion Criteria:  Maternal contraindication to fetoscopic surgery Preterm premature rupture of the membranes (PPROM) or condition strongly predisposing to PPROM or premature delivery Impossibility of remain close to the FETO center during the fetal occlusion period