Choosing an embryo for transfer

This chapter includes clinical cases, background, evidence-based practical management options, preventive measures, key-point summaries for choosing an embryo for transfer and answers to questions patients ask. In vitro fertilization (IVF) is considered successful when a singleton, full-term healthy baby is born. Successful embryo transfer requires a viable embryo, receptive endometrium and delicate transfer technique. Often, a number of embryos are created in IVF, and the challenge is to select the most viable one for transfer from the available cohort. Morphological scoring of gametes and embryos has been used since the early days of IVF. Over the past two decades embryo transfer has increasingly been shifted to the blastocyst stage despite limited evidence that later transfer improves live-birth rates compared with cleavage stage. Time-lapse technology allows essentially continuous evaluation of the embryos without removing them from the optimal culture conditions.