Table 2.
Comparison of cycle characteristics.
| Before PSM | After PSM | |||||||
|---|---|---|---|---|---|---|---|---|
| Group A | Group B | t/Z | P value | Group A | Group B | t/Z | P value | |
| Cycle number | 924 | 1984 | 915 | 915 | ||||
| COS cycle number | 0.096 | 0.757 | 0.179 | 0.672 | ||||
| First cycle | 751/81.28% | 1622/81.75% | 744/81.31% | 751/82.08% | ||||
| Second cycle | 173/18.72% | 362/18.25% | 171/18.69% | 164/17.92% | ||||
| Gn type | 48.317 | < 0.001 | 41.322 | < 0.001 | ||||
| Recombinant | 781/84.52% | 1637/82.51% | 775/84.70% | 756/82.62% | ||||
| Urinary | 44/4.76% | 227/11.44% | 42/4.59% | 106/11.58% | ||||
| Combined | 99/10.71% | 120/6.05% | 98/10.71% | 53/5.79% | ||||
| Gn starting dose | 169.16 ± 56.53 | 169.34 ± 57.53 | -0.079 | 0.937 | 168.99 ± 56.35 | 168.70 ± 56.88 | 0.108 | 0.914 |
| Gn total dose | 1500 (1200, 2025) |
1500 (1200, 2025) |
-2.775 | 0.006 | 1500 (1200, 2100) |
1500 (1200, 2025) |
0.111 | |
| Gn duration | 9 (8,10) | 9 (8, 10) | -2.724 | 0.006 | 9 (9, 10) | 9 (8, 10) | 0.107 | |
| GnRHant duration | 5.72 ± 1.47 | 6.01 ± 1.42 | -5.162 | < 0.001 | 5.71 ± 1.48 | 6.02 ± 1.41 | -4.521 | < 0.001 |
| GnRHant dose | 1.52 ± 0.47 | 1.54 ± 0.43 | -1.137 | 0.256 | 1.52 ± 0.47 | 1.55 ± 0.43 | -1.164 | 0.245 |
| LH level on trigger day (IU/L) | 1.54 (0.96, 2.66) | 1.32 (0.83, 2.21) | -4.585 | < 0.001 | 2.10 ± 1.85 | 1.93 ± 3.39 | 1.258 | 0.208 |
| P level on trigger day (nmol/L) | 2.40 (1.75, 3.50) | 2.30 (1.60, 2.10) | -4.115 | < 0.001 | 2.78 ± 1.50 | 2.63 ± 1.69 | 1.841 | 0.066 |
| E2 level on trigger day (pmol/L) | 45.287 | < 0.001 | 24.688 | < 0.001 | ||||
| < 3670 | 18/1.95% | 94/4.74% | 18/1.97% | 46/5.03% | ||||
| 3670–18350 | 581/62.88% | 1361/68.60% | 577/63.06% | 615/67.21% | ||||
| > 18350 | 200/21.65% | 259/13.05% | 196/21.42% | 135/14.75% | ||||
| Type of trigger | 18.67 | < 0.001 | 0.33 | 0.848 | ||||
| HCG | 595/64.39% | 1424/71.77% | 591/64.59% | 586/64.04% | ||||
| GnRHa | 219/23.70% | 400/20.16% | 217/23.72% | 214/23.39% | ||||
| Dual trigger | 110/11.90% | 160/8.06% | 107/11.69% | 115/12.57% | ||||
| Freeze-all cycles | 0.161 | 0.689 | 0.639 | 0.424 | ||||
| Reasons for freeze-all | ||||||||
| OHSS risk | 349/82.12% | 621/81.18% | 344/81.90% | 310/79.69% | ||||
| Others | 76/17.88% | 144/18.82% | 76/18.10% | 79/20.31% | ||||
| OPU number in COS cycle | 14.97 ± 7.76 | 13.96 ± 7.19 | 4.456 | 0.001 | 14.96 ± 7.75 | 14.17 ± 7.30 | 2.255 | 0.024 |
| Fertilization type | 2.024 | 0.364 | 0.53 | 0.767 | ||||
| IVF | 724/78.35% | 1514/76.31% | 717/78.36% | 705/77.05% | ||||
| ICSI | 154/16.67% | 374/18/85% | 162/17.70% | 174/19.01% | ||||
| IVF+ICSI | 46/4.87% | 96/4.84% | 36/3.93% | 36/3.93% | ||||
| Fertilization rate (%) | 76.21 ± 20.95 | 77.68 ± 19.95 | -1.812 | 0.07 | 76.31 ± 20.92% | 77.51 ± 20.17 | -1.251 | 0.211 |
| Cleavage rate (%) | 74.96 ± 21.02 | 76.41 ± 20.13 | -1.796 | 0.073 | 75.04 ± 21.00% | 76.26 ± 20.31 | -1.258 | 0.209 |
| Number of 2PN embryo(s) | 7.93 ± 5.04 | 7.66 ± 4.66 | 1.409 | 0.159 | 7.92 ± 5.03 | 7.75 ± 4.72 | 0.767 | 0.443 |
| Number of usable embryos (D3) | 6.22 ± 4.55 | 5.98 ± 4.09 | 1.422 | 0.155 | 6.23 ± 4.54 | 6.18 ± 4.15 | 0.226 | 0.821 |
| Number of good quality embryo | 2.20 ± 2.28 | 2.18 ± 2.16 | 0.206 | 0.836 | 1.34 ± 0.48 | 1.38 ± 0.49 | -0.483 | 0.629 |
| Cycles with fresh embryo transfer | 499/54.00% | 1219/61.44% | 14.423 | < 0.001 | 495/54.10% | 526/57.49% | 2.129 | 0.145 |
| Endometrial thickness | 10.39 ± 1.98 | 10.46 ± 1.96 | -0.786 | 0.432 | 10.40 ± 1.98 | 10.58 ± 1.99 | -1.744 | 0.081 |
| Number of embryos for ET | 1.963 | 0.161 | 1.815 | 0.178 | ||||
| N = 1 | 327/65.53% | 755/61.94% | 325/65.66% | 324/61.60% | ||||
| N = 2 | 172/34.47% | 464/38.06% | 180/34.34% | 202/38.40% | ||||
| Embryo stage | 0.003 | 0.956 | 0.025 | 0.874 | ||||
| Cleavage | 329/65.93% | 802/65.79% | 327/66.06% | 345/65.59% | ||||
| Blastocyst | 170/34.07% | 417/34.21% | 168/33.94% | 181/34.41% | ||||
PSM, propensity score matching; COS, controlled ovarian stimulation; Gn, gonadotropin; LH, luteinizing hormone; P, progesterone; E2, estrogen; HCG, human chorionic gonadotropin; GnRHa, gonadotropin releasing hormone agonist; OHSS, ovarian hyper-stimulation syndrome; OPU, oocytes pick up; IVF, in vitro fertilization; ICSI, intra-cytoplasmic sperm injection; 2PN, 2 pronucleus; D3, day 3; ET, embryo transfer.