Animals die during embryonic development. In C. elegans, often assayed as refractile eggs that fail to hatch; when applied to large-scale RNAi screens in C. elegans, more than 10% of embryos die.
Premature lethality during the adult stage. When applied to large-scale RNAi screens in C. elegans, this phenotype is present in at least 10% of analyzed worms, or at least 30% in the case of rrf-3 perturbed background.
Animals produce no or very few embryos as a result of experimental treatment. This is in contrast to sterility due to genetic perturbations (maternal effect sterility).