1. EA 73‐28 Université de Paris Paris France
2. AP‐HP, Department of Obstetrics and Fetal Medicine Hopital Necker‐E.M. Paris France
3. AP‐HP, Virology Laboratory Hopital Necker‐E.M. Paris France
4. AP‐HP, Neonatal Intensive Care Unit Hopital Necker‐E.M Paris France