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 circumstance, 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.
