At 34+0 weeks to 34 + 6 weeks, participants will undergo removal of the tracheal balloon. Balloon retrieval can be either by in utero puncture by ultrasound-guided percutaneous needling or fetoscopic retrieval. Uncomplicated retrieval patients will be managed as an outpatient with weekly fetal monitoring until delivery. In the event there is a need for emergent balloon removal prior to 34 weeks due to the development of preterm labor, shortening of the cervix, preterm rupture of membranes, abnormally vigorous lung response, or development of fetal hydrops, delivery by EXIT or cesarean section will be performed. If percutaneous puncture of balloon is unsuccessful prior to delivery, immediate bronchoscopy and establishment of airway will be performed. Maternal corticosteroids (betamethasone 12 mg intramuscularly and repeated once at 24 hours) will be administered 48 hours prior to fetoscopic balloon removal (due to risks of preterm delivery associated with instrumentation) or for impending preterm delivery.