Table 2 The propensity score matching of basic characteristics between once-vitrified group and re-vitrified group
Before matching | After matching | |||||
|---|---|---|---|---|---|---|
Once-vitrified group (n = 592) | Re-vitrified group (n = 55) | P | Once-vitrified group (n = 54) | Re-vitrified group (n = 54) | P | |
Female age at retrieval，years | 30.4 ± 4.4 | 29.3 ± 4.1 | 0.41 | 29.6 ± 4.1 | 29.3 ± 4.2 | 0.71 |
Primipara | 390 (65.9) | 15 (27.3) | <0.001 | 19 (35.2) | 15 (27.8) | 0.13 |
Body mass index, kg/m2 | 22.5 ± 3.4 | 22.2 ± 2.7 | 0.03 | 22.4 ± 3.4 | 22.2 ± 2.8 | 0.72 |
Basal FSH, mIU/mL | 7.5 ± 2.8 | 6.5 ± 1.5 | 0.06 | 7.1 ± 3.2 | 6.6 ± 1.5 | 0.25 |
Duration of infertility, years | 3.5 ± 2.7 | 3.7 ± 2.5 | 0.43 | 3.8 ± 2.5 | 3.7 ± 2.5 | 0.73 |
Insemination method | 0.44 | 0.82 | ||||
IVF | 446 (75.3) | 44 (80.0) | 41 (75.9) | 42 (79.6) | ||
ICSI | 146 (24.7) | 11 (20.0) | 13 (24.1) | 11 (20.4) | ||
Type of Infertility | 0.08 | 0.25 | ||||
Primary | 283 (47.8) | 33 (60.0) | 25 (46.3) | 32 (59.3) | ||
Secondary | 309 (52.2) | 22 (40.0) | 29 (53.7) | 22 (40.7) | ||
Endometrial preparation protocol | 0.81 | 0.57 | ||||
HRT | 491 (82.9) | 48 (87.3) | 43 (79.6) | 47 (87) | ||
Ovulation induction | 42 (7.1) | 3 (5.5) | 4 (7.4) | 3 (5.6) | ||
NC | 59 (10.0) | 4 (7.3) | 7 (13) | 4 (7.4) | ||
Cause of Infertility | 0.15 | 0.40 | ||||
Ovulation disorder | 38 (6.4) | 2 (3.6) | 3 (5.6) | 2 (3.7) | ||
Tubal factor | 253 (42.7) | 32 (58.2) | 26 (48.1) | 31 (57.4) | ||
Male factors | 62 (10.5) | 6 (10.9) | 3 (5.6) | 6 (11.1) | ||
Other factors | 239 (40.4) | 15 (27.3) | 22 (40.7) | 15 (27.8) | ||
Embryo quality | 0.23 | 0.51 | ||||
High quality embryos | 405 (68.4) | 42 (76.4) | 38 (70.4) | 42 (77.8) | ||
Good quality embryos | 187 (31.6) | 13 (23.6) | 16 (29.6) | 12 (22.2) | ||