Table 2.
Description of prognostic factors used to define good and poor prognosis groups in complete cases, before and after propensity score weighting
| Study groups before propensity score weighting | Study groups after propensity score weighting | |||||||
|---|---|---|---|---|---|---|---|---|
| Factor | Fresh transfer with AH (48,858 cycles) | Fresh transfer without AH (103,413 cycles) | P value | SMD | Fresh transfer with AH (148,723 cycles) | Fresh transfer without AH (153,114 cycles) | P value | SMD |
| Age | < 0.001 | 0.756 | 0.969 | < 0.001 | ||||
| < 38 | 25,423 (52.0) | 87,790 (84.9) | 110,802 (74.5) | 114,058 (74.5) | ||||
| ≥ 38 | 23,435 (48.0) | 15,623 (15.1) | 37,921 (25.5) | 39,056 (25.5) | ||||
| Live birth history | < 0.001 | 0.139 | 0.916 | 0.001 | ||||
| No | 25,464 (52.1) | 61,032 (59.0) | 84,431 (56.8) | 86,871 (56.7) | ||||
| Yes | 23,394 (47.9) | 42,381 (41.0) | 64,293 (43.2) | 66,244 (43.3) | ||||
| Embryo quality | < 0.001 | 0.187 | 0.018 | 0.018 | ||||
| Poor | 2803 (5.7) | 3755 (3.6) | 6528 (4.4) | 6440 (4.2) | ||||
| Fair | 12,788 (26.2) | 20,778 (20.1) | 34,259 (23.0) | 34,370 (22.4) | ||||
| Good | 33,267 (68.1) | 78,880 (76.3) | 107,936 (72.6) | 112,305 (73.3) | ||||
| Good or poor prognosis* | < 0.001 | 0.272 | 0.778 | 0.002 | ||||
| Good | 9591 (19.6) | 32,429 (31.4) | 41,192 (27.7) | 42,277 (27.6) | ||||
| Poor | 39,267 (80.4) | 70,984 (68.6) | 107,531 (72.3) | 110,837 (72.4) | ||||
P value < 0.05 denotes a difference in groups; SMD, standard mean difference; SMD < 0.1 implies balance; AH, assisted hatching
*Poor prognosis: one of the following poor prognosis criteria defined by: age 38 years or older, no history of a live birth, or poor-quality embryos. *Good prognosis: all of the following: age 37 years and younger, history of a live birth, and no poor-quality embryos