Table 1.
Cycle Characteristics Per Transfer
| Number of Vitrified-Warmed Blastocysts transferred | One | Two | p-value |
|---|---|---|---|
| Number of Transfers (Number of Patients) | 845 (711) | 851 (760) | -- |
| Patient Characteristics Per Transfer (± SD) | |||
| Age at Vitrification (years) | 33.7 ± 3.9 | 33.5 ± 4.0 | 0.34 |
| Age at Warming/Transfer (years) | 34.5 ± 3.9 | 34.0 ± 4.0 | 0.012 |
| Body Mass Index | 24.9 ± 5.0 | 25.4 ± 5.3 | 0.044 |
| Number Prior Transfers w/o Birth | 1.37 ± 1.26 | 1.40 ± 1.08 | 0.64 |
| Parity | 0.58 ± 0.65 | 0.36 ± 0.62 | <0.0001 |
| Prior Cycle Characteristics Per Transfer; N (%) | |||
| Freeze-all (No transfer) in Fresh Cycle | 81 (9.6) | 113 (13.3) | 0.017 |
| Live Birth from Fresh ET | 175 (22.9) | 60 (8.1) | <0.0001 |
| Infertility Diagnosis Per Transfer; N (%) transfers carrying diagnosis | |||
| Endometriosis | 61 (7.2) | 42 (4.9) | 0.053 |
| Male Factor | 315 (37.3) | 277 (32.6) | 0.041 |
| PCOS | 128 (15.2) | 176 (20.7) | 0.0030 |
| Tubal Factor | 108 (12.8) | 110 (12.9) | 0.93 |
| Uterine Factor | 47 (5.6) | 23 (2.7) | 0.0030 |
| Blastocyst Characteristics Per Transfer (± SD) | |||
| Day of Vitrification Post-Retrieval/Fertilization | 5.64 ± 0.57 | 5.60 ± 0.54 | 0.14 |
| Blastocysts Surviving Vitrification/Warming (%) | 95.6 ± 14.9 | 95.5 ± 12.6 | 0.84 |
| Intact Cells per Transferred Blastocyst (%) | 95.5 ± 5.4 | 95.2 ± 5.2 | 0.29 |
| Number of Vitrified Embryos Available for Transfer | 3.4 ± 3.0 | 4.6 ± 2.6 | <0.0001 |
| PGD/PGS; N (%) | 54 (6.4%) | 82 (9.6%) | 0.014 |