Prevention of multiple pregnancy following IVF in Spain.

Since the development of assisted reproduction techniques most countries have witnessed increased rates of multiple pregnancy. Despite the guidelines proposed by various scientific societies these rates continue to be abnormally high. In Spain, as in other Mediterranean countries, a greater number of embryos are transferred than in northern and central European countries and the incidence of multiple pregnancies is greater in comparison. Effective strategies must be established to prevent multiple pregnancy without reducing overall pregnancy rates. In the authors' institute, taking into account the authors' experience, the relevant literature, and despite the limitation of retrospective studies, it is recommended that a maximum of two embryos are transferred in young women with good quality embryos at the time of transfer. The transfer of three embryos is only recommended in women >or=38 years who have one or no good quality embryos available at the time of transfer. The responsibility for preventing multiple pregnancy lies with health professionals, who must be aware of the risks involved in twin and triplet pregnancy. Couples must be provided with objective information before starting an IVF cycle. Professional societies should highlight the problem and make suitable recommendations.