Table 4.
Relative risk of ovarian cancer in users by different types of hormonal contraception in women followed up to their first switch in hormonal contraception (that is, the no change cohort)
| No of person years | No of cancer events | Adjusted relative risk (95% CI)* | |
|---|---|---|---|
| Never use | 8 150 250 | 771 | 1.00 |
| Ever use (any hormonal contraception) | 7 183 430 | 293 | 0.73 (0.63 to 0.84) |
| Former use (any hormonal) | 2 590 322 | 164 | 0.85 (0.71 to 1.02) |
| Current or recent use (any hormonal) | 4 593 109 | 129 | 0.61 (0.50 to 0.74) |
| Current or recent use (combined OC) | 4 316 888 | 103 | 0.56 (0.45 to 0.70) |
| Current or recent use (progestogen only) | 276 221 | 26 | 0.87 (0.59 to 1.29) |
| Current or recent use of combined hormonal contraception—oral | |||
| Norethisterone, 50 µg ethinylestradiol | 36 494 | 4 | 1.35 (0.50 to 3.61) |
| Levonorgestrel, 50 µg ethinylestradiol | 47 335 | 6 | 1.21 (0.54 to 2.71) |
| Norethisterone, 30-35 µg ethinylestradiol | 116 090 | 7 | 1.30 (0.62 to 2.76) |
| Levonorgestrel, 30-35 µg ethinylestradiol | 519 113 | 11 | 0.33 (0.18 to 0.61) |
| Desogestrel, 20-30 µg ethinylestradiol | 988 952 | 17 | 0.45 (0.27 to 0.73) |
| Gestodene, 20-35 µg ethinylestradiol | 1 887 047 | 42 | 0.57 (0.41 to 0.79) |
| Drospirenone, 20-35 µg ethinylestradiol | 188 928 | 5 | 1.08 (0.44 to 2.64) |
| Norgestimate, 35 µg ethinylestradiol | 375 778 | 11 | 0.75 (0.41 to 1.37) |
| Cyproterone, 30 µg ethinylestradiol | 142 147 | 0 | — |
| Estradiol valerate, dienogest | 1022 | 0 | — |
| Current or recent use of combined hormonal contraception—non-oral | |||
| Patch | 2253 | 0 | — |
| Vaginal ring | 11 729 | 0 | — |
| Current or recent use of progestogen-only contraception—oral | |||
| Norethisterone | 66 934 | 4 | 0.62 (0.23 to 1.64) |
| Levonorgestrel | 6972 | 1 | 1.16 (0.16 to 8.23) |
| Desogestrel | 12 155 | 0 | — |
| Current or recent use of progestogen-only contraception—non-oral | |||
| MPA depot | 7321 | 3 | 6.56 (2.11 to 20.40) |
| Implant | 10 575 | 0 | — |
| LNG-IUS | 172 265 | 18 | 0.84 (0.53 to 1.35) |
LNG-IUS=levonorgestrel intrauterine system; MPA=medroxyprogesterone acetate.
*
Adjusted for calendar year, parity, age, education, tubal sterilisation, hysterectomy, endometriosis, polycystic ovary syndrome, and family history of breast or ovarian cancer.