Table 1 Characteristics of the patients at baseline and outcomes of controlled ovarian hyperstimulation
Baseline characteristics | OHSS group (n=385) | Control group | |||
|---|---|---|---|---|---|
Unmatched (n=6356) | P value | Matched 1:4 (n=1540) | P value | ||
Age (years), mean ±SD | 29.3±3.8 | 30.3±4.3 | <0.001 | 29.4±4.0 | 0.585 |
BMI (kg/m2) | 21.8±2.7 | 22.5±3.0 | <0.001 | 21.8±2.7 | 0.997 |
Duration of infertility (years) | 3.8±2.4 | 4.2±3.0 | 0.002 | 3.8±2.6 | 0.964 |
Baseline FSH (mIU/ml) | 6.5±1.7 | 7.1±2.2 | <0.001 | 6.5±1.8 | 0.876 |
Baseline LH (mIU/ml) | 6.0±4.3 | 5.4±3.3 | 0.005 | 6.0±4.0 | 0.939 |
AFC | 14.7±5.8 | 12.8±6.0 | <0.001 | 14.5±6.4 | 0.588 |
Indications for IVF | |||||
 Unexplained factors (%) | 10 (2.6) | 320 (5.0) | 0.031 | 42 (2.7) | 0.888 |
 Anovulatory disorders (includes PCOS) | 67 (17.4) | 563 (4.9) | <0.001 | 216 (14.0) | 0.094 |
 Tubal factors | 157 (40.8) | 2923 (46.0) | 0.046 | 670 (43.5) | 0.334 |
 Endometriosis-associated | 7 (1.8) | 137 (2.2) | 0.657 | 25 (1.6) | 0.789 |
 Male factors | 111 (28.8) | 2060 (32.4) | 0.144 | 449 (29.2) | 0.900 |
 Pelvic inflammatory disease | 3 (0.8) | 56 (0.9) | 1 | 13 (0.8) | 1.000 |
 Multiple factors | 33 (8.6) | 605 (9.5) | 0.538 | 138 (9.0) | 0.810 |
E2 level on hCG trigger day (pg/ml) | 4484.9±1905.8 | 4098.5±2715.2 | <0.001 | 4521.6±4030.0 | 0.795 |
No. of oocytes retrieved | 12.2±2.9 | 10.5±3.8 | <0.001 | 12.2±4.0 | 0.906 |
Multiple gestations, no. (%) | 179 (46.5) | 1719 (27.1) | <0.001 | 725 (47.0) | 0.837 |