In assisted reproductive technology (ART), there is a common occurrence that mature oocytes have two polar bodies without two pronuclei after insemination, which named nonpronuclear. The pronuclei of those oocytes may appear in advance or delay at the time of fertilization checking, so the assessment of fertilization is inconclusive. Due to the confusion and controversy of nonpronuclear-derived embryos (named nonpronuclear embryos) in clinical application at present, nonpronuclear embryos are usually discarded which may result in wasting available embryos even decreasing the utilization of the eggs. In recent years, nonpronuclear embryos get more and more attention in ART and have made certain research progress. The aim of this review is to summarize the mechanisms, influence factors, inheritance, embryonic development, clinical outcomes, and other applications about nonpronuclear embryos. The review may provide more basis for the reasonable application.