| Table 9. In vitro fertilization (IVF) intra-cycle characteristics and assisted reproductive technology (ART) outcomes according to age (n=494). | |||
| < 35 years (n=238) |
≥ 35 years (n=256) |
p-value | |
|---|---|---|---|
| ICSI (%) | 141 (59.2) | 117 (45.7) | 0.003a |
| Gonadotropin dose (IU) | 2148.43±797.01 | 2472.63±1075.47 | <0.001b |
| Number of stimulation days | 9.76±1.90 | 9.80±2.27 | NSb |
| Number of follicles | 16.30±10.51 | 11.40±9.30 | <0.001b |
| Number of COC | 11.93±7.41 | 9.49±7.77 | <0.001b |
| Oocyte immaturity rate (%) | 17.14±16.11 | 18.36±19.38 | NSb |
| Number of 2PN oocytes | 5.57±4.01 | 4.59±3.98 | 0.007b |
| Fertilization rate (%) | 48.91±25.04 | 51.81±28.93 | NSb |
| Cleavage rate (%) | 98.00±7.89 | 97.30±10.21 | NSb |
| Blastocyst rate (%) | 8.70±15.34 | 5.34±13.01 | 0.032b |
| Number of obtained embryos | 2.65±1.98 | 2.40±1.94 | NSb |
| Number of IVF cycles with freeze all [n (%)] | 115 (48.3) | 94 (36.9) | 0.010a |
| Number of criopreserved embryos | 1.67±2.15 | 1.39±2.06 | NSb |
| Positive βHCG [n (%)] | 138 (58.0) | 107 (41.8) | <0.001a |
| Clinical pregnancy rate (%) | 47.4 | 29.9 | <0.001a |
| Cumulative clinical pregnancy (%) | 52.9 | 35.5 | <0.001a |
| LBR (%) | 42.5 | 23.7 | <0.001a |
| CLBR (%) | 47.1 | 28.4 | <0.001a |
| Endometrial thickness on the day of the last monitoring (mm) | 9.94±2.15 | 9.83±1.95 | NSb |
| Endometrial thickness on oocyte pick-up day (mm) | 11.02±2.37 | 10.06±2.02 | 0.006b |
Data expressed as mean±standard deviation. p-value < 0.05 was considered statistically significant. ICSI - Intracytoplasmatic sperm injection; IU - International units; COC - cumulus-oocyte complexes; 2PN - two pronucleated; IVF - in vitro fertilization; βHCG - human chorionic gonadotropin hormone; LBR - live birth rate; CLBR - Cumulative live birth rate; NS - not statistically different; a - Chi-square test; b - One Way ANOVA.