Move follows the death of a 10-day-old baby in December who had being given the supplement Uvesterol D, health officials said.
Woman in her 30s on holiday in south-west France arrested after baby's father reported death and doctor declared it was not from natural causes.
Mayor of Champlan denies refusing to bury baby but apologises as saga continues to spark row and child is buried in nearby town.
Right-wing mayor of Champlan near Paris provoked outrage for blocking burial of the baby, who will now be laid to rest in neighbouring town.
Yoan Delorme was in jail when his son was born and the mother did not put either parent's name on the birth certificate before the adoption.