Table 3.
Standardised incidence ratios (SIRs) for ovarian, breast, and corpus uteri cancer among 225 786 women who underwent assisted reproduction in Great Britain, 1991-2010, stratified by various factors*
| Factor | Follow-up (No of person years) | Breast cancer† | Corpus uteri cancer‡ | Ovarian cancer§ | |||||
|---|---|---|---|---|---|---|---|---|---|
| No of observed cancers | SIR (95% CI) | No of observed cancers | SIR (95% CI) | No of observed cancers | SIR (95% CI) | ||||
| Age at first treatment (years) | |||||||||
| <25 | 48 187 | 14 | 1.32 (0.72 to 2.21) | 0 | 0.00 (0.00 to 6.97) | 6 | 2.21 (0.81 to 4.80) | ||
| 25-29 | 381 964 | 185 | 0.92 (0.79 to 1.06) | 10 | 1.24 (0.60 to 2.29) | 64 | 2.16 (1.67 to 2.76) | ||
| 30-34 | 866 351 | 774 | 0.95 (0.89 to 1.02) | 43 | 1.19 (0.86 to 1.60) | 142 | 1.52 (1.28 to 1.80) | ||
| 35-39 | 714 056 | 1033 | 0.97 (0.91 to 1.03) | 72 | 1.22 (0.96 to 1.54) | 134 | 1.23 (1.03 to 1.45) | ||
| 40-44 | 218 767 | 479 | 1.02 (0.93 to 1.12) | 33 | 0.96 (0.66 to 1.35) | 50 | 1.05 (0.78 to 1.38) | ||
| ≥45 | 28 463 | 93 | 1.09 (0.89 to 1.34) | 6 | 0.68 (0.25 to 1.48) | 9 | 0.97 (0.45 to 1.85) | ||
| Trend across categories | — | P=0.13 | P=0.28 | P<0.001 | |||||
| Infertility cause | |||||||||
| Any female factor | 1 109 593 | 1279 | 0.95 (0.90 to 1.00) | 97 | 1.25 (1.02 to 1.53) | 246 | 1.66 (1.46 to 1.88) | ||
| Male factor only | 757 063 | 774 | 0.92 (0.86 to 0.99) | 41 | 0.91 (0.65 to 1.24) | 98 | 1.05 (0.85 to 1.27) | ||
| Unexplained | 326 495 | 416 | 1.10 (1.00 to 1.21) | 16 | 0.78 (0.45 to 1.27) | 40 | 0.96 (0.69 to 1.31) | ||
| Unrecorded | 64 638 | 109 | 1.49 (1.24 to 1.80) | 10 | 2.53 (1.21 to 4.66) | 21 | 2.59 (1.60 to 3.95) | ||
| History of endometriosis | |||||||||
| Yes | 181 279 | 214 | 0.98 (0.86 to 1.12) | 9 | 0.75 (0.35 to 1.43) | 55 | 2.31 (1.74 to 3.01) | ||
| No | 2 076 509 | 2364 | 0.98 (0.94 to 1.02) | 155 | 1.15 (0.98 to 1.34) | 350 | 1.31 (1.17 to 1.45) | ||
| History of tubal disease | |||||||||
| Yes | 710 522 | 826 | 0.96 (0.90 to 1.03) | 59 | 1.23 (0.93 to 1.58) | 158 | 1.68 (1.43 to 1.97) | ||
| No | 1 547 266 | 1752 | 0.98 (0.94 to 1.03) | 105 | 1.06 (0.87 to 1.29) | 247 | 1.25 (1.10 to 1.41) | ||
| History of ovulatory problems | |||||||||
| Yes | 311 523 | 357 | 0.92 (0.83 to 1.02) | 39 | 1.59 (1.13 to 2.17) | 55 | 1.28 (0.97 to 1.67) | ||
| No | 1 946 265 | 2221 | 0.99 (0.95 to 1.03) | 125 | 1.02 (0.85 to 1.21) | 350 | 1.41 (1.26 to 1.56) | ||
| Duration of infertility at last cycle (years) | |||||||||
| <2 | 133 067 | 171 | 0.95 (0.82 to 1.11) | 6 | 0.55 (0.20 to 1.20) | 28 | 1.44 (0.96 to 2.09) | ||
| 2-3 | 439 560 | 527 | 1.05 (0.96 to 1.14) | 23 | 0.82 (0.52 to 1.23) | 73 | 1.30 (1.02 to 1.64) | ||
| 4-5 | 447 739 | 520 | 0.99 (0.90 to 1.07) | 30 | 1.03 (0.70 to 1.47) | 74 | 1.27 (1.00 to 1.60) | ||
| 6-7 | 271 583 | 316 | 0.91 (0.82 to 1.02) | 27 | 1.38 (0.91 to 2.01) | 60 | 1.61 (1.23 to 2.07) | ||
| 8-9 | 151 580 | 197 | 0.95 (0.83 to 1.10) | 16 | 1.34 (0.77 to 2.18) | 36 | 1.64 (1.15 to 2.27) | ||
| ≥10 | 209 751 | 322 | 0.95 (0.85 to 1.05) | 37 | 1.68 (1.18 to 2.31) | 57 | 1.60 (1.21 to 2.08) | ||
| Unrecorded | 324 953 | 404 | 1.07 (0.97 to 1.18) | 18 | 0.92 (0.54 to 1.45) | 42 | 1.02 (0.74 to 1.38) | ||
| Trend across categories | — | P=0.20 | P<0.001 | P=0.15 | |||||
| Total No of stimulated cycles | |||||||||
| 0 (“natural cycle” only) | 90 973 | 142 | 0.88 (0.74 to 1.04) | 8 | 0.66 (0.28 to 1.29) | 17 | 0.99 (0.58 to 1.59) | ||
| 1 | 1 041 791 | 1203 | 0.98 (0.92 to 1.03) | 89 | 1.29 (1.04 to 1.59) | 196 | 1.44 (1.25 to 1.66) | ||
| 2 | 473 125 | 585 | 1.01 (0.93 to 1.09) | 29 | 0.91 (0.61 to 1.30) | 87 | 1.38 (1.10 to 1.70) | ||
| 3-4 | 306 137 | 420 | 1.03 (0.93 to 1.13) | 24 | 1.06 (0.68 to 1.58) | 53 | 1.23 (0.92 to 1.60) | ||
| ≥5 | 66 149 | 107 | 1.08 (0.89 to 1.31) | 7 | 1.24 (0.50 to 2.55) | 17 | 1.67 (0.97 to 2.67) | ||
| Trend across categories | — | P=0.07 | P=0.93 | P=0.86 | |||||
| Total number of live births at last cycle completion | |||||||||
| 0 | 1 009 134 | 1299 | 0.99 (0.93 to 1.04) | 122 | 1.61 (1.34 to 1.92) | 222 | 1.57 (1.37 to 1.79) | ||
| 1 | 718 998 | 843 | 1.03 (0.96 to 1.10) | 24 | 0.53 (0.34 to 0.79) | 114 | 1.25 (1.03 to 1.50) | ||
| ≥2 | 249 685 | 314 | 0.92 (0.82 to 1.03) | 11 | 0.54 (0.27 to 0.96) | 34 | 0.93 (0.64 to 1.30) | ||
| Unrecorded | 414 | 1 | 1.82 (0.05 to 10.13) | 0 | 0.00 (0.00 to 99.86) | 0 | 0.00 (0.00 to 49.93) | ||
| Trend across categories | — | P=0.56 | P<0.001 | P=0.001 | |||||
| Any multiple birth as recorded at last cycle completion | |||||||||
| Yes | 232 824 | 258 | 1.10 (0.97 to 1.24) | 5 | 0.42 (0.14 to 0.99) | 33 | 1.23 (0.85 to 1.73) | ||
| No | 1 745 409 | 2199 | 0.98 (0.94 to 1.02) | 152 | 1.17 (1.00 to 1.38) | 337 | 1.39 (1.24 to 1.54) | ||
| Time since last treatment (years) | |||||||||
| 0-3 | 687 180 | 525 | 1.04 (0.95 to 1.13) | 28 | 1.39 (0.92 to 2.00) | 99 | 1.54 (1.25 to 1.88) | ||
| 3-6 | 486 191 | 529 | 1.04 (0.95 to 1.13) | 29 | 1.28 (0.85 to 1.83) | 73 | 1.27 (1.00 to 1.60) | ||
| 6-10 | 444 324 | 657 | 1.00 (0.93 to 1.08) | 38 | 1.07 (0.76 to 1.47) | 84 | 1.24 (0.99 to 1.53) | ||
| 10-15 | 296 445 | 590 | 0.93 (0.86 to 1.01) | 45 | 0.99 (0.72 to 1.33) | 86 | 1.39 (1.11 to 1.71) | ||
| ≥15 | 64 091 | 156 | 0.86 (0.73 to 1.01) | 17 | 0.98 (0.57 to 1.57) | 28 | 1.57 (1.05 to 2.27) | ||
| Trend across categories | — | P=0.01 | P=0.12 | P=0.74 | |||||
*
See supplementary appendix for results excluding the first 12 months of follow-up.
†
Breast cancer=ICD-9 codes 1740-1749, 2330, and 2383; ICD-10 codes C500-C509, D050-D059, and D486.
‡
Corpus uteri cancer=ICD-9 codes 1820-1828 and ICD-10 code C54.
§
Ovarian cancer=ICD-9 codes 1830-1839 and 2362; ICD-10 codes C56, C570-C574, C481, C482, and D391.