Summary of findings 1. Levonorgestrel‐releasing intrauterine device compared to low dose combined oral contraceptive for uterine fibroids.
| Levonorgestrel‐releasing intrauterine device compared to low dose combined oral contraceptive for uterine fibroids | ||||||
| Patient or population: women with uterine fibroids Setting: university hospital Intervention: levonorgestrel‐releasing intrauterine device (LNG‐IUS) Comparison: low dose combined oral contraceptive (COC) | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with COC | Risk with LNG‐IUS | |||||
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Uterine fibroid‐related symptoms (change in abnormal uterine bleeding, measured at 12 months, with the alkaline hematin test) |
With COC, the menstrual blood loss (MBL) dropped, on average, by 13.4%. | With LNG‐IUS, the change in MBL was, on average, 77.50% higher (70.44% higher to 84.56% higher). | ‐ | 44 (1 RCT) | ⊕⊝⊝⊝ Very lowa,b | MD 77.50% (95% CI 70.44 to 84.56) |
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Uterine fibroid‐related symptoms (change in abnormal uterine bleeding, measured at 12 months, with the pictorial blood assessment chart (PBAC)) |
MBL dropped by an average of 53.5% with COC | With LNG‐IUS, the MBL was, on average, 34.50% higher (11.59 higher to 57.41 higher) | ‐ | 44 (1 RCT) | ⊕⊝⊝⊝ Very lowa,b | MD 34.50% (95% CI 11.59 to 57.41) |
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Uterine fibroid‐related symptoms (haemoglobin level, at 12 months; higher = better) |
The mean haemoglobin level with COC was 10.2 g/dL | The mean haemoglobin level with LNG‐IUS was 1.50 g/dL higher (0.85 higher to 2.15 higher) | ‐ | 44 (1 RCT) | ⊕⊝⊝⊝ Very lowa,b | MD 1.50 g/dL (95% CI 0.85 to 2.15) |
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Fibroid size (percentage of change, at 12 months; higher = better) |
With COC, the size of the fibroid shrank, on average, by 2.4% | With LNG‐IUS, the average reduction in fibroid size was 1.90% higher (12.24 lower to 16.04 higher) | ‐ | 44 (1 RCT) | ⊕⊝⊝⊝ Very lowa,b |
MD 1.90% (95% CI ‐12.24 to 16.04); skewed data |
| Adverse events | ‐ | ‐ | ‐ | ‐ | ‐ | Study did not report |
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; MD: mean difference | ||||||
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GRADE Working Group grades of evidence High quality: further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect, and may change the estimate. Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: we are very uncertain about the estimate. | ||||||
aDowngraded by one level due to risk of bias; unclear allocation concealment, unclear blinding, and unclear selective reporting. bDowngraded by two levels due to imprecision; one study with small sample size.