All plants genetically modified to be insect resistant or herbicide tolerant undergo a risk assessment, which includes evaluating potential adverse impacts on nontarget arthropods (insects and related animals). Major groups tested include pollinators (e.g., honey bees and bumble bees), predators (e.g., lady beetles and green lacewings) and parasites (e.g., Diaeretiella rapae, an aphid parasite). In addition, soil-dwelling animals, like earthworms, isopods, Collembola, nematodes and protozoa, have been tested.
Please read this review of the effects of GMOs on bees and insects (Annual Review of Entomology, volume 50, pages 271–92). The study, published in 2005 — nine years after the first commercial releases of genetically modified plants — concluded, “The extensive testing on non-target, plant-feeding insects and beneficial species that has accompanied the long-term and wide-scale use of Bt plants has not detected significant adverse effects.”
There are additional studies on how GMOs impact insects. Rosi-Marshall and others published a study in the Proceedings of the National Academy of Sciences that showed that laboratory feeding of Bt corn by-products reduced growth and increased mortality of nontarget caddisflies. This study generated many conversations in the scientific community (see here, here and here). Jensen and others also looked at caddisflies in a 2010 study (Environmental Entomology, volume 39, number 2, pages 707–14) and concluded, “Overall, our results provide evidence that adverse effects to aquatic non-target shredders involve complex interactions arising from plant genetics and environment that cannot be ascribed to the presence of Cry1Ab proteins.”
You can find a similar response regarding bee health here.