In 2007, there were 56,817 assisted reproductive technology (ART) treatment cycles undertaken in Australian and New Zealand. Of these cycles, 17.4% resulted in a live delivery (the birth of at least one liveborn baby). In total, 10,856 liveborn babies were born following ART treatment undertaken in 2007. The most important recent trend in ART treatment has been the reduction in the rate of twins and triplets births, with the multiple delivery rate falling from 18.7% in 2003 to 10.0% in 2007. This trend has been associated with an increase in the proportion of ART treatment cycles using single embryo transfer, from 32.0% in 2003 to 63.7% in 2007.