Summary of findings 6. HT FET versus HT + GnRHa FET.
| HT FET versus other regimens for primary or secondary subfertility | ||||||
| Population: women with primary or secondary subfertility Settings: assisted reproductive technology clinics Intervention: HT FET Comparison: HT plus GnRHa trigger | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| HT + GnRHa FET | HT FET | |||||
| Live birth rate per woman | 742 per 1000 | 223 per 1000 (103 to 463) | OR 0.10 (0.04 to 0.30) | 75 (1 study) | ⊕⊕⊝⊝ Low1,2 | Only 33 events |
| Miscarriage rate per woman | 48 per 1000 | 31 per 1000 (18 to 53) | OR 0.64 (0.37 to 1.12) | 991 (6 studies) | ⊕⊕⊝⊝ Low3,4 | ‐ |
| Ongoing pregnancy rate per woman | 132 per 1000 | 207 per 1000 (85 to 424) | OR 1.72 (0.61 to 4.85) | 106 (1 study) | ⊕⊝⊝⊝ Very low4,5 | Only 18 events |
| Multiple pregnancy rate per woman | No data available | |||||
| *The basis for the assumed risk is the mean control group risk across studies. 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; FET: frozen‐thawed embryo transfer; GnRHa: gonadotrophin releasing hormone agonist;HT: hormone therapy; OR: odds ratio | ||||||
| GRADE Working Group grades of evidence High quality: We are very confident that the true effect lies close to that of the estimate of the effect Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect | ||||||
1Downgraded one level due to serious imprecision: single study, few events. 2Downgraded one level due to serious inconsistency: clinical pregnancy rate in this study was higher than in six other studies in the same analysis (none of which reported live birth) and this study accounted for all inconsistency in the analysis for clinical pregnancy (I2 = 46%). 3Downgraded one level due to serious imprecision: confidence intervals compatible with benefit in HT‐only arm or with no effect. 4Downgraded one level due to serious risk of bias: method of allocation concealment unclear in all studies/only study. 5Downgraded two levels due to very serious imprecision: single study, few events.