Table 2.
Baseline patient characteristics.
| Variable | IVIg group (n = 24) | Control group (n = 40) | P-value |
|---|---|---|---|
| Primary RIF (RIF-1) | |||
| Age at embryo transfer (years) | 35.5 (26–44) | 34.0 (24–41) | 0.083 |
| 35, n (%) | 12 (50) | 28 (70) | |
| > 35, n (%) | 12 (50) | 12 (30) | |
| BMI (kg/m2) | 22.0 (18.3–34) | 23.3 (19–31.1) | 0.25 |
| < 25, n (%) | 16 (66.6) | 22 (55.0) | 1 |
| 25–34.9, n (%) | 8 (33.3) | 12 (30.0) | |
| Missing data, n (%) | 0 | 6 (15.0) | |
| # blastocyst transfers before index ET* | 5.0 (4–9) | 4.0 (3–6) | < 0.001*** |
| 3–4 blastocyst transfers, n (%) | 7 (29.2) | 32 (80) | |
| ≥ 5 blastocyst transfers, n (%) | 17 (70.8) | 8 (20) | |
| Total # failed ET before index ET** | 6.0 (4–17) | 4.0 (3–9) | < 0.001*** |
| AMH (ng/mL) | 2.79 (0.12–8.24) (n = 19) | 2.53 (0.66–10) (n = 28) | 0.8 |
| Reason for IVF (%) | |||
| Unexplained | 12 (50) | 23 (57.5) | 0.51 |
| Explained (one patient may have several) | 12 (50) | 17 (42.5) | |
| Male factor, n (%) | 10 (41.7) | 22 (55.0) | |
| Tubal factor, n (%) | 0 | 1 (2.5) | |
| Diminished ovarian reserve, n (%) | 4 (16.7) | 0 | |
| Pre-implantation genetic screening, n (%) | 5 (20) | 5 (12.5) | |
| Egg donation, n (%) | 2 (8.3) | 0 | |
| PCOS, n (%) | 3 (12.5) | 5 (12.5) | |
| Endometriosis, n (%) | 2 (8.3) | 6 (15) | |
| Variable | IVIg group (n = 25) | Control group (n = 54) | P-value |
|---|---|---|---|
| Secondary RIF (RIF-2) | |||
| Age (years) | 36.0 (32–42) | 36.0 (26–44) | 0.28 |
| 35, n (%) | 10 (40) | 25 (46.3) | 0.65 |
| > 35, n (%) | 15 (60) | 29 (53.8) | |
| BMI (kg/m2) (range) | 22.0 (17.9–32) | 23.0 (19–32.6) | 0.89 |
| < 25, n (%) | 17 (68.0) | 19 (35.2) | 0.37 |
| 25–34.9, n (%) | 8 (32.0) | 13 (24.1) | |
| Missing data, n (%) | 0 | 18 (33.3) | |
| Gestation prior to index pregnancy (number) | 3.0 (1–5) | 2.0 (1–5) | 0.065 |
| Parity prior to index pregnancy (mean, SD) | 0.48 (+ / − 0.714) | 0.63 (+ /– 0.560) | 0.16 |
| # of blastocyst transfers before index ET* | 4.0 (3–8) | 4.0 (3–10) | 0.14 |
| 3–4 blastocyst transfers, n (%) | 13 (52) | 37 (68.5) | 0.21 |
| ≥ 5 blastocyst transfers, n (%) | 12 (48) | 17 (31.5) | |
| Total # failed ET before index ET** | 5.0 (3–12) | 4.0 (3–13) | 0.005*** |
| AMH (ng/ml) | 2.64 (0.65–10.4) (n = 18) | 2.73 (0.56–16.5) (n = 31) | 0.79 |
| Reason for IVF (%) | – | – | – |
| Unexplained | 16 (64) | 40 (74.1) | 0.43 |
| Explained (one patient may have several) | 9 (36) | 14 (25.9) | |
| Male factor, n (%) | 11 (44) | 36 (66) | |
| Tubal factor, n (%) | 2 (8) | 10 (18.5) | |
| Diminished ovarian reserve, n (%) | 3 (12) | 1 (1.9) | |
| Pre-implantation genetic screening, n (%) | 4 (16) | 15 (27.8) | |
| Egg donation, n (%) | 0 | 0 | |
| PCOS, n (%) | 1 (4) | 15 (27.8) | |
| Endometriosis, n (%) | 6 (24) | 9 (16.7) | |
All p-values were calculated using the Mann Whitney U test for continuous variables (expressed as median and (minimum–maximum value)) or the Fisher exact test or Student T-test for categorical variables (+ /– indicated mean and standard deviation).
BMI body mass index, ET embryo transfer, PCOS polycystic ovarian syndrome, IVIg intravenous immunoglobulin.
*Only high-quality blastocyst ( 3BB).
**Total blastocysts (including day 3, morula and lesser quality blastocysts (< 3BB).
***Statistically significant.