It is very uncertain whether rhLH changes miscarriage rate per woman compared with uhCG (very low certainty).
Brief co‐incubation showed no clear difference in miscarriage rate per randomized woman compared with standard insemination (low certainty).
Ultrasound‐guided embryo transfer showed no clear difference in miscarriage (per woman randomised) compared with clinical touch (moderate certainty).
Metformin showed no clear difference in miscarriage rate per woman compared with placebo or no treatment (low certainty).
Low‐dose aspirin showed no clear difference in miscarriage rate per woman compared with placebo or no treatment (low certainty).
Metabolomics showed no clear difference in miscarriage (Loss of pregnancy before 20 completed weeks of gestation) compared with non metabolomics (low certainty).
It is very uncertain whether assisted hatching changes miscarriage rate per woman randomised compared with no assisted hatching (very low certainty).
Endometrial injury showed no clear difference in miscarriage per woman randomised: sensitivity analysis (no high risk) compared with control (low certainty).
It is very uncertain whether higher changes miscarriage per woman randomised: sensitivity analysis (including… compared with lower degree of injury (very low certainty).
Endometrial injury showed no clear difference in miscarriage per woman randomised (studies at low risk of selection… compared with control (moderate certainty).