| Table 1. Patient characteristics, cycle parameters, and serum β-hCG levels (mean ± SD). | ||||
| Total ofpatients(mean ± SD) | Negativebiochemicalpregnancy(mean ± SD) | Positivebiochemicalpregnancy(mean ± SD) | ||
| N | 116 | 55 | 61 | |
| Age (years) | 37.8±4.4 | 37.6±4.6 | 38.0±4.2 | 0.656 |
| No. of embryos transferred | 1.8±0.5 | 1.7±0.5 | 1.9±0.5 | 0.050 |
| β-hCG day 5 (IU/L) | 11.8±15.4 | 1.6±2.9 | 21.0±16.3 | < 0.001 |
| E2 day 5 (pg/mL) | 198.6±109.1 | 180.9±93.5 | 213.5±119.4 | 0.109 |
| P4 day 5 (ng/mL) | 56.0±100.5 | 60.8±109.6 | 51.8±92.6 | 0.639 |
| β-hCG day 10 (IU/L) | 174.3±228.3 | 1.7±4.0 | 330.0±218.9 | < 0.001 |
| E2 day 10 (pg/mL) | 224.8±161.8 | 175.2±101.9 | 266.3 ±189.7 | 0.004 |
| P4 day 10 (ng/mL) | 53.7±107.3 | 52.8±107.9 | 54.5±107.8 | 0.939 |
Total patient data were divided into two groups according to biochemical pregnancy outcome (β-hCG levels on day 10 ≥ 25 IU/L).
*Student t-test comparing means between subgroups of negative and positive biochemical pregnancy based on β-hCG levels on day 10.