Summary of findings 5. IUI in a stimulated cycle compared to IUI in a natural cycle for unexplained subfertility.
| IUI in stimulated cycle compared to IUI in natural cycle for unexplained subfertility | ||||||
| Patient or population: participants with unexplained subfertility Settings: fertility clinic Intervention: IUI in a stimulated cycle Comparison: IUI in a natural cycle | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| IUI in a natural cycle | IUI in a stimulated cycle | |||||
| Live birth rare per couple (all cycles) | 139 per 1000 | 250 per 1000 (165 to 361) | OR 2.07 (1.22 to 3.50) | 396 (4 studies) | ⊕⊕⊝⊝ lowa,b | ‐ |
| Multiple pregnancy rate per couple | Not estimable (no events in control group) | ‐ | OR 3.00 (0.11 to 78.27) | 39 (1 study) | ⊕⊕⊝⊝ lowc | ‐ |
| Pregnancy rate per couple (all cycles) | 63 per 1000 | 302 per 1000 (36 to 831) | OR 6.43 (0.56 to 73.35) | 26 (1 study) | ⊕⊕⊝⊝ lowc | ‐ |
| Ovarian hyperstimulation syndrome rate per woman ‐ not measured | See comment | See comment | Not estimable | ‐ | See comment | No events in intervention and control groups |
| Miscarriage rate per couple | Not estimable (no events in control group) | ‐ | OR 5.21 (0.19 to 141.08) | 26 (1 study) | ⊕⊕⊝⊝ lowc | ‐ |
| Ectopic pregnancy rate per couple | Not estimable (no events in control group) | ‐ | OR 6.48 (0.33 to 127.09) | 211 (1 study) | ⊕⊝⊝⊝ very lowb,c | ‐ |
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (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; OR: Odds ratio; | ||||||
| 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 for serious imprecision: small sample size with a low event rate. bDowngraded by one level for serious risk of bias: sequence generation and allocation concealment rated as 'unclear' for the largest/larger study. cDowngraded by two levels for very serious imprecision: small sample size with a low event rate and effect estimate with a wide confidence interval.