Does anticoagulation in pregnancy stop blood clotting? does treatment stop dvt completely

Yes but...: Yes but nothing is perfect. We always have to weigh risk vs benefit. If we are aggressive with anticoagulant you are unlikely to have clots. If too aggressive you could bleed. So the proper dosing with close monitoring is required.

No.: Dvt can occur while on anticoagulation and also while pregnant and on anticoagulation. If either of these occurs, it usually means that the anticoagulation has been at unacceptable levels. You need close monitoring and probably, should be followed by a hematologist.