The rationale for fetal therapy in severe congenital diaphragmatic hernia (CDH) is to restore adequate lung growth for neonatal survival.

Prenatal tracheal occlusion (TO) obstructs the normal egress of lung fluid during pulmonary development leading to increased lung tissue stretch, increased cell proliferation, and accelerated lung growth. European colleagues have developed foregut endoscopy and techniques to position and remove endoluminal tracheal balloons in utero. Recently, the Belgium group published summary results of FETO showing an improved survival in 175 patients with isolated left CDH from 24% to 49%.

The goal of this pilot study is to study the feasibility of implementing FETO therapy in the most severe group of fetuses with left CDH Observed/expected lung-to-head ratio < 25%(O/E LHR < 25%).

Inclusion Criteria:

• Pregnant women age 18 years and older, who are able to consent
• Singleton pregnancy

Fetal

• Normal Karyotype
• Fetal Diagnosis of Isolated Left CDH with liver up
• Gestation at enrollment prior to 29 wks plus 6 days
• SEVERE pulmonary hypoplasia with Ultra Sound O/E LHR < 25%

Exclusion Criteria:

• Pregnant women <18 years of age.
• Maternal contraindication to fetoscopic surgery or severe maternal medical condition in pregnancy
• Technical limitations precluding fetoscopic surgery
• Rubber latex allergy
• Preterm labor, cervix shortened (<15 mm at enrollment or within 24 hours of FETO balloon insertion procedure) or uterine anomaly strongly predisposing to preterm labor, placenta previa
• Psychosocial ineligibility, precluding consent
• Diaphragmatic hernia: right-sided or bilateral, major associated anomalies, isolated left-sided with the O/E LHR ≥ 25%
• Inability to remain at FETO site during time period of tracheal occlusion, delivery and postnatal care