Background: Since the most recent Cochrane review on hMG versus rFSH for controlled ovarian hyperstimulation following a long down-regulation protocol, several new trials have emerged. Methods: We conducted a systematic review and meta-analysis of randomized trials comparing the effectiveness of hMG versus rFSH following a long down-regulation protocol in IVF-ICSI cycles, on the primary outcome of live birth per woman randomized, as well as several other secondary outcomes. Searches were conducted in MEDLINE, EMBASE, Science Direct, Cochrane Library and databases of abstracts (last search January 2007). Results: Seven randomized trials, consisting of a total of 2159 randomized women, were identified. A meta-analysis of these trials showed a significant increase in live birth rate with hMG when compared with rFSH (relative risk, RR = 1.18, 95% CI: 1.02-1.38, P=0.03). The heterogeneity test was non-significant (P= 0.97), suggesting that there was no statistical inconsistency between the seven studies. The pooled risk difference (RD) for the outcome of live birth rate was 4% (95% CI: 1-7%) for these study populations. There was an increase in clinical pregnancy rates with hMG when compared with rFSH (RR = 1.17, 95% CI 1.03-1.34). No significant differences were noted for gonadotrophin use, spontaneous abortion, multiple pregnancy, cancellation and ovarian hyperstimulation syndrome rates. Conclusions: For the populations in the randomized trials, hMG was associated with a pooled 4% increase in live birth rate when compared with rFSH in IVF-ICSI treatment following a long down-regulation protocol.