Effect of the new legislation and single-embryo transfer policy in Turkey on assisted reproduction outcomes: preliminary results.

New legislation concerning assisted reproduction treatments was introduced in Turkey in March 2010 in order to reduce the number of multiple pregnancies. This new legislation limits the number of embryos to be transferred to one under 35 years of age in the first or second treatment cycles and to two in the third or further cycles or for 35 and older ages. The aim of this multicentre study was to investigate the effect of this new law on clinical pregnancy and multiple pregnancy rates.