The clinical materials of infertile female patients who underwent in vitro fertilization-embryo transfer （IVF-ET） assisted fertility treatment in our department were retrospectively analyzed， and the patients were divided into <30 years old group （48 cases， 439 embryos）， 30 years old≤patients’ age<40 years old group （129 cases，1 019 embryos） and ≥40 years old group （48 cases， 176 embryos） according to their ages. All embryos were cultured in the Time-lapse culture system until Day 3； the developmental dynamics of early embryos were observed， and the number of eggs obtained， fertilization rates， cleavage rates， number of available embryos， number of excellent embryos， etc were compared among three groups； at the same time， the relationship between age and embryonic developmental arrest was also explored.

Compared with≥40 years old group， the number of eggs obtained， the number of available embryos， and the number of high-quality embryos of the patients in <30 years old group and 30 years old≤ patient’s age<40 years old group were increased （P<0.05）； there were statistical differences in time from fertilization to division into 3 cells stages（t3）， time from fertilization to division into 4 cells stages（t4），fertilization time to division into 5 cells stages（t5），time from fertilization to division into 6 cells stages（t6）， time from 2 cells to 3 cells （cc2） among three groups （P<0.05）； the time from fertilization to division into 2 cells stages（t2） and t6 in 30 years old≤patients’ age<40 years old group were longer than those in <30 years old group （P<0.05）； t3 in ≥40 years old group was longer than that in <30 years old group and 30 years old ≤patients’ age<40 yeras old group （P<0.05）， and t3 in 30 years old ≤patients’ age <40 years old group were also longer than those in <30 years old group （P<0.05）； t4 and t5 in ≥40 years old group were longer than those in <30 years old group （P<0.05）， and cc2 in ≥40 years old group was longer than those in <30 years old group and 30 years old≤patients age<40 years old group （P<0.05）； there were no statistical differences in time from fertilization to the disappearance of the two pronucleis（tPNF），time from fertilization to division into 7 cells stages（t7）， time from fertilization to division into 8 cells stages（t8）， time from 3 cells to 4 cells（s2）， time from 5 cells to 8 cells（s3）， time from 3 cells to 5 cells（cc3） among three groups （P>0.05）.Compared with <30 years old group and 30 years old ≤patients’ age <40 years old group， the fragmentation rate of patients in ≥40 years old group was increased （P<0.05）， the incidence of other abnormal division events had a tendency to increase， but there were no statistically significant differences（P>0.05）； compared with <30 years old group and 30 years old≤patients’ age<40 years old group， the proportions of embryos developed to 5 cells， 6 cells， 7 cells and 8 cells in ≥40 years old group were decreased （P<0.05）.

The patients’ age has a certain influence in the developmental dynamics of embryos， with the increase of the patients’ age， the probability of developmental arrest of embryos increases.