The twin epidemic in infertility care - Why do we persist in transferring too many embryos?

The epidemic of iatrogenic multiple births as a result of infertility treatment are responsible for an unacceptable high incidence of maternal, perinatal and childhood morbidity and mortality. Healthcare costs due to infertility therapy are too high and this may lead to social and political concern. The introduction of single embryo transfer (SET) was a real breakthrough, but was only accepted in most European countries and Japan. The United States, Latin America and most developing countries still have high multiple pregnancy rates. The most common argument for not performing SET are the high costs associated with ART procedures. Competition between ART centres to achieve and publish the highest success rates is another major factor. But things have changed: vitrification methods for cryopreservation are responsible for a better survival and increased success rate with frozen-embryo transfer, our knowledge to select the best embryo for SET is increasing and the growing concern of health care providers and governments can be expected in the near future. Infertility specialists are supposed to deliver healthy, preferably singleton babies at the lowest cost. Misuse of science still reveals the dark side of ART in too many centres. There is enough evidence that reimbursement policies providing accessible ART to infertile couples can decrease the potential harm from multiple pregnancies substantially unless we succeed to provide simplified IVF at affordable prices.