Table 1.
Embryos included in the study. The cohort consisted of cleavage-stage embryos, transferred fresh on day 3 of development, and blastocysts, either day-5 or day-6, transferred fresh or vitrified/warmed. Pregnancy rates (PR), clinical pregnancy rates (CPR) and live birth rates (LBR) are expressed in percentages (%) and in absolute numbers (n). LBR for day 3 embryos were lower compared to blastocysts (p=0.034) and D6 transfers lower than D5 transfers (p=0.04)
| Day of transfer | Type | Embryos (n) | PR % (n) | CPR % (n) | LBR % (n) |
|---|---|---|---|---|---|
| D3 | Fresh | 116 | 31.0 (36) | 28.4 (33) | 25.0 (29) |
| D5 | Fresh | 287 | 55.7 (160) | 44.9 (129) | 43.2 (124) |
| D5 | Frozen | 285 | 54.4 (155) | 38.9 (111) | 36.5 (104) |
| D6 | Frozen | 80 | 35.0 (28) | 32.5 (26) | 32.5 (26) |
| Total | 768 | 49.5 (380) | 38.9 (299) | 36.8 (283) |