Table 1 Demographic data and parameters of the oocyte freezing cycles
From: Usage and cost-effectiveness of elective oocyte freezing: a retrospective observational study
|  | Total | Age ≤ 35 years | Age 36–39 years | Age ≥ 40 years | P value |
|---|---|---|---|---|---|
Cases/Cycles, n/N | 645/840 | 189/221 | 263/324 | 193/295 | Â |
Two or more retrieval cycles | 126 (19.5) | 28 (14.8) | 44 (16.7) | 54 (28.0) | 0.005 |
Single status | 596 (92.4) | 175 (92.6) | 245 (93.2) | 176 (91.2) | 0.731 |
Childless | 626 (97.1) | 186 (98.4) | 254 (96.6) | 186 (96.4) | 0.803 |
Body mass index, kg/m2 | 20.3 (19.0–21.9) | 20.0 (18.7–21.5) | 20.3 (18.9–21.8) | 21.7 (19.2–22.5) | 0.136 |
Bologna criteria for POR | 124 (19.2) | 25 (13.2) | 29 (11.0) | 70 (36.3) |  < 0.001 |
Ovarian disease | |||||
Endometriosis | 53 (8.2) | 22 (11.6) | 13 (4.9) | 18 (9.3) | 0.088 |
Dermoid cyst | 11 (1.7) | 7 (3.7) | 3 (1.1) | 1 (0.5) | 0.105 |
Other benign ovarian tumors | 12 (1.9) | 5 (2.6) | 4 (1.5) | 3 (1.6) | 0.952 |
Prior ovarian surgeries | 38 (5.9) | 18 (9.5) | 10 (3.8) | 10 (5.2) | 0.099 |
Oocyte retrieval and freezing | |||||
Retrieved oocytes/case | 12 (7–18) | 16 (10–21) | 13 (8–20) | 9 (5–14) |  < 0.001 |
Retrieved MII oocytes/case | 8 (4–14) | 11 (6–16) | 9 (5–15) | 6 (3–10) |  < 0.001 |
Retrieved MII/total oocytes, % | 73.9 (58.8–87.2) | 75.0 (62.5–87.0) | 75.0 (60.0–87.5) | 71.0 (55.0–87.5) | 0.396 |
Frozen oocytes/case | 11 (7–17) | 15 (9–20) | 12 (7–19) | 8 (4–13) |  < 0.001 |
Frozen MII oocytes/case | 9 (5–14) | 12 (7–17) | 10 (6–16) | 6 (3–10) |  < 0.001 |