摘要Objective To explore the relationship between the patterns of pronucleus and embryo development and pregnancy potential in the pronuclear stageMethods According to the number and distribution of nucleolar precursor bodies, the embryos at pronuclear stage were classified into 6 pronuclear patterns from 0 to 5, 16～18 h after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). For each pattern, the subsequent embryonic morphology and the pregnancy rate were analyzed. Results Embryos of Pattern 0 developed to significantly more embryos with good quality and higher pregnancy potential than the embryos developing from other patterns (83.14% and 76.11% respectively, P<0.05). The pregnancy rate was decreased as less embryos of Pattern 0 were transferred . The pregnancy rate of the groups of only Pattern 0, with Pattern 0, and without Pattern 0 were 48.08%, 32.14% and 21.28% respectively (P<0.05).Conclusions The pronuclear patterns are of the predictive value of embryo development and pregnancy potential, which can be used as a new tool for the selection of embryos in IVF and ICSI.