Supplementary Material for: INTRAUTERINE TREATMENT IN TWO FETUSES AFFECTED BY CYSTIC FIBROSIS.TO WHOM AND SINCE WHEN?REPORT OF CASES.

Introduction: Cystic fibrosis (CF) is an autosomal recessive disease asociated to low survival disease into adulthood. The appearance of the cystic fibrosis transmembrane conductance regulator (CFTR) therapy has revolutionized the management and the prognosis of this patients with an improvement in the pancreatic and lung function with a much better quality of life. More women with CF are considering being mothers. Other clinical scenario is the prenatal diagnosis of fetus with CF. Three cases reports have been published suggesting that CFTR therapy during pregnancy in fetuses affected by CF might prevent prenatal meconium ileous (MI), which are the one who have a higher risk of gastrointestinal morbidity and long-term complications. Case presentation: We present two cases reports in which the diagnosis of CF occurred during intrauterine life and treatment with CFTR therapy was administered to healthy pregnant women in order to reduce the risk MI in their fetuses. In both cases the diagnosis suspicion was by ultrasound findings with a genetic confirmed diagnosis by amniocentesis. In the first case, the mother received the CTFR therapy during five weeks and MI was not developed by the newborn. In the second one, the mother received the treatment only for a week and MI could not be avoided. Conclusion: This clinical situation has special ethical considerations, since a drug is being administered through compassionate use to a women who does not need it. The fundamental reason is the lack of authorization for the use of these drugs in newborns but in adults. We hope that these two clinical cases, together with those already published, will increase the knowledge and experience of using this drug in this context helping with the management of pregnant women with fetuses affected by CF in order to reduce associated complications.