I been thinking about this for while to me amazon shouldn't need men to reproduce. After Diana birth one of the goddess should have said something like this I was so move by your request of wanting a child that I will allow amazons who want motherhood to revice it. The kids will not be blood related to the mother only by the amazon heritage. The 100 amazons that want motherhood will get it.

Wasn't that kinda what happened in Gail's run? Spontaneously Pregnant Amazons... Remember how that turned out?

No how did that turn out. If I did I run like the one you talking about I about do that they would have to complete a challenge or win a fight before having a baby.

IIRC In the Perez background, children lost at sea were brought to the island and would be raised as new Amazons to replace attrition (accidental death, invasions etc) It's also possible that once the island is known they might accept women who want to join them.