Are US results for assisted reproduction better than the rest? Is it a question of competence or policies?

A comparison of nationally published 2006 data from the USA, UK and Australia and New Zealand (ANZ) was performed. Although live births/cycle was higher in USA, live birth/embryo transferred was significantly higher in ANZ (18.2%) compared with both USA and UK (13.8%) (P < 0.001). The multiple rates were significantly lower in ANZ (12.0%) compared with USA (30.7%) and UK (25.2%) (P < 0.001). The incidence of oocyte donation was significantly higher in the USA (11.1%) than in ANZ (2.8%) and UK (3.9%) (P < 0.001). There was significantly higher cycle cancellation in USA (11.5%) compared with the UK (6.8%) and ANZ (9.5%) (P < 0.001). The incidence of frozen embryo transfer cycles was significantly higher in ANZ (59%) compared with both UK (24%) and USA (22%) (P < 0.001). The total live birth rate from fresh and frozen cycles for the same year was significantly higher in ANZ at 32.0% compared with the UK at 28.8% (P < 0.001) with half the multiple rate. It is argued that the USA's higher success rates are explained by policy (transferring higher number of embryos) and selection issues (cancelling or avoiding poor responders) rather than being a matter of clinical competence.