Eight trials in total, comprising one double-blind and 7 non-blinded trials, were included.
None of the trials offered treatment with GIFT, so the analysis was restricted to IVF treatment. There was no significant heterogeneity in the treatment effect across all trials (p = 0.58).
The overall OR in favour of FSH for clinical pregnancy rates per cycle start, oocyte retrieval and ET were 1.71 (95% CI 1.12 to 2.62), 1.69 (95% CI 1.10 to 2.59) and 1.70 (95% CI 1.10 to 2.62) respectively and represented an overall absolute treatment effect of 8.5, 8.0 and 8.3% respectively. These estimates were statistically significant and represented an improvement over hMG of 62.5, 51.6 and 50.3% respectively.
There was insufficient information in the trials on rates of spontaneous abortion, OHSS and multiple pregnancy to allow an overview of these secondary outcomes.