ABSTRACT
A single, live birth is the ultimate goal of in vitro fertilization (IVF). However, the low probability of such an outcome in the early days of IVF became the root of multi-embryo transfers in order to increase the odds for a viable singleton. The rapid progression of physicians and embryologists along parallel learning curves resulted in IVF implantation rates that by now surpass natural implantation. This circum-stance, in turn, led to increasingly higher rates of singleton deliveries, concomitant with an untoward increase in multiple pregnancies, a phenomenon, coupled with the exponential utilization of IVF, which became the basis of an epidemic-proportion increase in higher-order multiple pregnancies and overpopulation of high-risk clinics, antepartum units and above all neonatal intensive-care units across the USA.
