Patient and cycle characteristics
From January 2016 to December 2019, 9832 frozen-thawed D3 embryo
transfer cycles from a total of 23366 were analyzed, including 6013
short culture cycles (2-3 h of post-thawed culture) and 3819 long
culture cycles (18-20 h of post-thawed culture) (Figure S1). The female
age, duration of infertility and body-mass index were 20-45 years, 0-25
years and 12-42 kg/m² respectively. The detailed cycle characteristics
of the different groups are shown in Table S1. Significant differences
of average age between L and S groups were observed in the <
35, 35-39 and total age groups
(P /CI = 0.001/0.112-0.416,
0.046/-0.218–0.002, 0.000/0.226-0.630 respectively), and the
differences of body-mass index, natural cycle rate, primary infertility
rate and duration of infertility were not significant in all age groups.