Look at these websites. Mature flukes release ova , some from the oral cavity as you have described. When they hatch miracidia are released - some are motile and other need to develop before becoming motile.
Chapter 6. The Trematodes (Flukes)
Fasciolopsis buski (giant intestinal fluke) is a ... Size of Ova: Fasciola hepatica: Cosmopolitan: Sheep: Bile Ducts ... Eggs become embryonated in water , eggs release ...
LESSON 4: TREMATODES (FLUKES)
... located on the ventral surface posterior to the oral suc***. There is no body cavity. ... name: Blood Fluke, Manson's Blood Fluke Size of Parasite: Ova:up to 180 mm Ö
faculty.unlv.edu/klaassen/PAR-LAB4FLUK.pdf ∑ PDF file
Hope this helps. Hulda Clark wrote that using Wormwood , green Black-Walnut tincure and cloves would kill Fasciola buski in 3 to 5 days and she advised using a Zapper. Use good bathroom and kitchen sanitation. Cook all food. Treat all family members and pets. Avoid all organic solvents.