Table 4. Factors associated with poor fertilisation in women who had at least one oocyte mixed or injected with partner sperm.
|
IVF
|
ICSI
|
|||||
|---|---|---|---|---|---|---|
| Univariable risk ratio of poor fertilisation 1 | Multivariable2 risk ratio (99% CI) of poor fertilisation | P value 3 | Univariable risk ratio of poor fertilisation 1 | Multivariable2 risk ratio (99% CI) of poor fertilisation | P value 3 | |
| (N=62,239 women) | (N=55, 725 women included in the analysis) | (N=49, 119 women) | (N=44,043 women included in analysis) | |||
| All women | 4500 (7.2%) | 4006 (7.2%) | 1518 (3.1%) | 1321 (3.0%) | ||
| Women’s age (years) | P=0.024 | P=0.001 | ||||
| 18-34 | 1.0 | 1.0 | 1.0 | 1.0 | ||
| 35-37 | 1.00 (0.91, 1.09) | 0.93 (0.85, 1.03) | 1.16 (0.98, 1.38) | 0.96 (0.80, 1.15) | ||
| 38-39 | 1.02 (0.90, 1.14) | 0.90 (0.79, 1.02) | 1.64 (1.35, 1.99) | 1.19 (0.96, 1.48) | ||
| 40-42 | 1.11 (0.98, 1.26) | 0.93 (0.81, 1.07) | 2.07 (1.69, 2.54) | 1.27 (1.01, 1.59) | ||
| 43-44 | 1.33 (1.05, 1.68) | 0.99 (0.76, 1.28) | 2.83 (2.00, 4.00) | 1.45 (0.99, 2.11) | ||
| 45-50 | 1.96 (1.41, 2.74) | 1.35 (0.94, 1.95) | 3.79 (2.25, 6.37) | 1.65 (0.94, 2.90) | ||
| Duration (years) | P<0.001 | P=0.035 | ||||
| <1 | 0.78 (0.56, 1.07) | 0.95 (0.68, 1.31) | 0.88 (0.49, 1.58) | 0.95 (0.54, 1.68) | ||
| 1-3 | 0.87 (0.79. 0.95) | 0.90 (0.82, 0.99) | 0.95 (0.81, 1.12) | 0.96 (0.81, 1.13) | ||
| 4-6 | 1.0 | 1.0 | 1.0 | 1.0 | ||
| 7-9 | 1.15 (1.01, 1.30) | 1.24 (1.09, 1.40) | 1.12 (0.89, 1.41) | 1.09 (0.87, 1.38) | ||
| 10-12 | 1.03 (0.87, 1.22) | 1.19 (1.00, 1.41) | 1.42 (1.09, 1.85) | 1.35 (1.03, 1.77) | ||
| >12 | 0.99 (0.83, 1.17) | 1.19 (0.99, 1.43) | 1.21 (0.91, 1.62) | 1.06 (0.78, 1.44) | ||
| Cause of infertility | P<0.001 | P=0.224 | ||||
| Tubal disease only | 0.60 (0.54, 0.67) | 0.64 (0.57, 0.71) | 1.22 (0.85, 1.75) | 1.26 (0.86, 1.85) | ||
| Ovulatory only | 1.09 (0.97, 1.23) | 1.07 (0.94, 1.21) | 1.57 (1.07, 2.30) | 1.43 (0.96, 2.13) | ||
| Male Factor Only | 1.29 (1.14, 1.47) | 1.29 (1.13, 1.48) | 1.08 (0.87, 1.34) | 1.16 (0.93, 1.45) | ||
| Unexplained | 1.0 | 1.0 | 1.0 | 1.0 | ||
| Endometriosis | 0.75 (0.62, 0.91) | 0.71 (0.58, 0.86) | 1.08 (0.54, 2.14) | 0.92 (0.43, 1.98) | ||
| Cervical Factors only | 1.78 (0.67, 4.73) | 1.58 (0.55, 4.48) | - 4 | -4 | ||
| Combination of Known factors | 0.93 (0.81, 1.07) | 0.94 (0.81, 1.08) | 1.14 (0.89, 1.47) | 1.17(0.90, 1.52) | ||
| Previous pregnancy | P<0.001 | P=0.006 | ||||
| Yes | 1.0 | 1.0 | 1.0 | 1.0 | ||
| No | 1.33 (1.23, 1.43) | 1.30 (1.19, 1.42) | 0.99 (0.86, 1.13) | 1.19 (1.01, 1.39) | ||
| Number of oocytes retrieved | P<0.001 | P<0.001 | ||||
| 1-4 | 2.03 (1.83, 2.26) | 2.03 (1.81, 2.27) | 5.85 (4.83, 7.09) | 5.29 (4.31, 6.51) | ||
| 5-9 | 1.10 (0.99, 1.22) | 1.09 (0.98, 1.21) | 1.49 (1.21, 1.83) | 1.40 (1.13, 1.75) | ||
| 10-14 | 1.0 | 1.0 | 1.0 | 1.0 | ||
| 15-19 | 0.95 (0.82, 1.09) | 0.94 (0.81, 1.09) | 0.76 (0.56,1.05) | 0.73 (0.54, 1.02) | ||
| 20+ | 1.10 (0.95, 1.28) | 1.08 (0.92, 1.27) | 0.81 (0.56, 1.16) | 0.82 (0.56, 1.19) | ||
1 Poor fertilisation defined as failure or less than 20% of oocytes fertilised
2 Multivariable risk ratio is adjusted for all variables listed
3 P values obtained from multivariable model.
4 Women receiving ICSI with cause of infertility recorded as cervical factors only (n=4), were excluded from the analysis