And two seemed to work without affecting hormone levels. And one of those two drugs, chlorpromazine, is classified as a presumed human reproductive toxicant by the Netherlands due to its potential damage to human fertility; all the work so far has involved animal models.
Chlorpromazine, usually used to treat schizophrenia, is not a good candidate for birth control because of its psychoactive effects. But it does prove the concept: fruit fly ovaries can be used effectively to screen compounds for non-hormonal birth control.