Table 2. Patient characteristics and outcomes of the included cycles with double embryo transfer.
| Variable | Included cycles (n = 2038) | Prognosis | P-valuea | ||
|---|---|---|---|---|---|
| Favorable (n = 812) | Average (n = 906) | Poor (n = 320) | |||
| Maternal ageb,d | 37.8 ± 2.7 | 37.6 ± 2.6 | 38.0 ± 2.8 | 37.9 ± 2.7 | 0.007 |
| Maternal BMI | 21.2 ± 2.5 | 21.1 ± 2.5 | 21.2 ± 2.5 | 21.2 ± 2.4 | 0.957 |
| Cause of infertility | |||||
| Tubal pathology | 682 (33.5) | 251 (30.9) | 322 (35.5) | 109 (34.1) | 0.124 |
| Endometriosis | 195 (9.6) | 76 (9.5) | 89 (9.8) | 30 (9.4) | 0.940 |
| Male factorc,d | 713 (35.0) | 265 (32.6) | 316 (34.9) | 132 (41.3) | <0.001 |
| Unexplainedb,d | 230 (11.3) | 114 (14.0) | 90 (9.9) | 26 (8.1) | 0.004 |
| Othersb,d | 218 (10.7) | 106 (13.1) | 89 (9.8) | 23 (7.2) | 0.008 |
| Type of infertility (%) | 0.069 | ||||
| Primary infertility | 1,665 (81.7) | 647 (79.7) | 760 (83.9) | 258 (80.6) | |
| Secondary infertility | 373 (18.3) | 165 (20.3) | 146 (16.1) | 62 (19.4) | |
| Fertilization method (%)b,d | 0.006 | ||||
| IVF | 1,257 (61.7) | 534 (65.8) | 541 (59.7) | 182 (56.9) | |
| ICSI | 781 (38.3) | 278 (34.2) | 365 (40.3) | 138 (43.1) | |
| Length of embryo cryopreservation (month) | 5.7 ± 3.8 | 5.5 ± 3.9 | 5.8 ± 3.7 | 5.8 ± 4.1 | 0.414 |
| Survival rate (%) | 4,119/4,213 (97.8) | 1,642/1,681 (97.7) | 1,832/1,874 (97.8) | 645/658 (98.0) | 0.879 |
| Damaged blastomere (%) | 0.367 | ||||
| Yes | 221 (10.8) | 80 (9.9) | 108 (11.9) | 33 (10.3) | |
| No | 1,817 (89.2) | 732 (90.1) | 798 (88.1) | 287 (89.7) | |
| Endometrial thickness (mm) | 9.1 ± 1.6 | 9.1 ± 1.6 | 9.1 ± 1.6 | 8.9 ± 1.7 | 0.136 |
| Endometrial preparation (%) | 0.367 | ||||
| Natural cycles | 126 (6.2) | 41 (5.0) | 65 (7.2) | 20 (6.3) | |
| HRT cycles | 1,912 (93.8) | 771 (95.0) | 841 (92.8) | 300 (93.7) | |
| No. of good-quality embryos transferredb,c,d | 1.1 ± 0.9 | 1.9 ± 0.1 | 0.8 ± 0.6 | 0 | <0.001 |
| Clinical pregnancyb,c,d | 816 (40.0) | 374 (46.1) | 346 (38.2) | 96 (30.0) | <0.001 |
| Implantation rateb,c,d | 1,008/4076 (24.7) | 470/1,624 (28.9) | 430/1,812 (23.7) | 108/640 (16.9) | <0.001 |
| Twin pregnancyc,d | 192 (23.5) | 102/374 (27.3) | 78/346 (22.5) | 12/96 (12.5) | 0.008 |
| Live birthb,c,d | 734 (36.0) | 335 (41.3) | 318 (35.1) | 81 (25.3) | <0.001 |
Notes:
a
P-value for global comparison between the three groups.
b
Significant comparison between women with favorable and average prognosis.
c
Significant comparison between women with average and poor prognosis.
d
Significant comparison between women with favorable and poor prognosis.