1. National Referral Centre for Twin-to-Twin Transfusion Syndrome; Paris-Descartes University, Necker-Enfants-Malades Hospital, APHP; Paris France
2. Obstetrics and Fetal Medicine Department; Necker-Enfants-Malades Hospital, APHP, Paris V University; Paris France
3. Maternal Fetal Medicine Unit; University of Brescia, Spedali Civili di Brescia; Brescia Italy
4. Neonatology Department; Necker-Enfants-Malades Hospital, APHP, Paris V University; Paris France
5. Pediatric Cardiology Department; Necker-Enfants-Malades Hospital, APHP, Paris V University; Paris France