Table 1 Patient characteristics

maternal age (years)

35.3 ± 0.37

35.0 ± 0.21

ns (p = 0.499)

IVF cycles (n)

31

149

–

ICSI cycles (n)

91

305

–

cycles with splitting IVF/ICSI (n)

2

21

–

oocytes (n)

11.02 ± 0.46

10.91 ± 0.24

ns (p = 0.826)

mature oocytes (MII) in ICSI cycles (n)

8.83 ± 0.45

8.67 ± 0.23

ns (p = 0.743)

PN/cycle

6.44 ± 0.28

6.16 ± 0.13

ns (p = 0.343)

cycles with calcium ionophore

9 (7.3%)

40 (8.4%)

ns (p = 0.854)

cycles with assisted hatching

6 (4.8%)

23 (4.8%)

ns (p = 1.0)

cycles with polar body biopsy

7 (5.6%)

12 (2.5%)

ns (p = 0.087)

no of transferred embryos

SET: N = 12

DET: N = 110

TET: N = 2

SET: N = 82

DET: N = 387

TET: N = 6

s for SET (p = 0.038)

ns for DET (p = 0.061)

ns for TET (p = 0.673)

mean no of transferred embryos

1.92 ± 0.03

1.84 ± 0.02

s (p = 0.023)

transferred ideal embryos

99/238 (41.6%)

385/874 (44.1%)

ns (p = 0.508)

transferred embryos with timely developmental stage (day 4 = morula; day 5 = blastocyst)

99/238 (41.6%)

809/874 (92.9%)

s (p < 0.001)

frozen PN/cycle

2.04 ± 0.26

1.81 ± 0.12

ns (p = 0.388)

frozen embryos/cycle

0.32 ± 0.06

0.37 ± 0.03

ns (p = 0.462)