If fetus inherits factor v Leiden from paternal carrier is there any treatment to avoid miscarriage? Cld it be dangerous to mom as well?

No. The concern about Factor V Leiden is when the mother is the carrier, not the father or fetus. Current studies show an inconsistent association with Factor V Leiden and pregnancy loss or stillbirth when mom is the carrier. You should have no concerns about potential problems with the pregnancy with dad as the carrier.