Ge 2008.
Methods | Randomised controlled trial | |
Participants | 760 women from China having IVF with fewer than five failed cycles of ART with normal baseline FSH concentration. Those participants with uterine abnormality or low fertilisation capacity (rate of fertilisation less than 20% and late ICSI following fertilisation failure of IVF) were excluded Mean age: Fresh, 31.08 in AH, 30.44 control; Frozen, 31.84 in AH, 30.66 control |
|
Interventions | Laser thinning to about 50% of the initial ZP thickness AH: 387 women with fresh embryos, 100 women with frozen‐thawed embryos Control: 373 women with fresh embryos, 100 women with frozen‐thawed embryos |
|
Outcomes | Implantation rate, pregnancy rate and live birth | |
Notes | Unclear if power calculation performed ITT not stated Published as full paper | |
Risk of bias | ||
Bias | Authors' judgement | Support for judgement |
Random sequence generation (selection bias) | Unclear risk | Women were randomised according to a randomisation list based on sequential numbers in sealed envelopes |
Allocation concealment (selection bias) | Low risk | Both patients and the clinician were blinded to group allocation |
Blinding (performance bias and detection bias) All outcomes | Unclear risk | Not stated in the text |
Incomplete outcome data (attrition bias) All outcomes | Low risk | Fresh embryo transfer cycles: a total of 831 IVF/ICSI cycles were performed during the study period. Of these, 772 met the inclusion criteria but 12 participants abandoned embryo transfer for various reasons such as avoiding potential risks of ovarian hyperstimulation syndrome Frozen‐thawed embryo transfer: a total of 245 frozen‐thawed cycles were also performed, of which 45 were excluded either because they didn't meet the criteria of the study or embryo transfer was abandoned |
Selective reporting (reporting bias) | Unclear risk | Original protocol not viewed |