Table 1 Characteristics of the couples and biological parameters of the IVF cycles used for the primary objective. Data are reported as means and standard deviations (SD). BMI body mass index, IVF in vitro fertilization, IU International Unit, PN pronuclei.
Parameter | Monophasic (5%) O2 strategy | Biphasic (5–2%) O2 strategy | p value |
|---|---|---|---|
Couples (n)/cycles (n) | 120/120 | 120/120 | – |
Women’s age (years) | 33.5 ± 4.6 | 35.3 ± 4.4 | < 0.01 |
Women’s BMI (kg/m2) | 23.7 ± 4.3 | 23.8 ± 4.2 | 0.91 |
Men’s age (years) | 36.4 ± 6.1 | 37.9 ± 6.1 | 0.06 |
Duration of infertility (months) | 44.3 ± 29.1 | 43.7 ± 29.4 | 0.86 |
Total number of IVF cycles (n) | 1.6 ± 0.9 | 2.7 ± 1.0 | < 0.01 |
Number of women smoking (cigarettes/week) | 25/120 50 ± 35 | 24/120 50 ± 35 | 1 1 |
Number of men smoking (cigarettes/week) | 42/120 72 ± 39 | 42/120 75 ± 40 | 1 0.77 |
Primary dose of gonadotrophins (IU) | 215.2 ± 82.9 | 234.2 ± 82.2 | 0.06 |
Total dose of gonadotrophins (IU) | 2274.5 ± 979.1 | 2559.6 ± 1077.3 | 0.06 |
Duration of stimulation (days) | 10.4 ± 1.5 | 10.8 ± 1.9 | 0.06 |
Retrieved oocytes (n) | 10.9 ± 5.0 | 11.1 ± 6.0 | 0.86 |
Oocytes (n) inseminated or injected (IVF/ICSI) | 247/843 | 219/860 | 0.18 |
2 PN embryos at day 1 (n) | 5.7 ± 3.3 | 5.6 ± 3.4 | 0.52 |
Embryos at day 3 (n) | 6.4 ± 3.7 | 6.2 ± 3.8 | 0.49 |
Total blastocyst rate (n, %) | 44.4% (230/518) | 54.8% (297/542) | 0.049 |
Usable blastocyst rate (n, %) | 21.8% (113/518) | 32.8% (178/542) | 0.002 |
Usable blastocyst rate at day 5 (n, %) | 9.1% (47/518) | 19.9% (108/542) | 1.53 × 10–5 |
Usable blastocyst rate at day 6 (n, %) | 12.7% (66/518) | 12.9% (70/542) | 0.94 |
