An advance in infertility treatment involves growing human embryos in the laboratory to a later "blastocyst" stage before transferring them into the uterus following in vitro fertilization. We offer blastocyst culture to infertile couples undergoing IVF or ICSI by allowing developing embryos to grow undisturbed to blastocyst stage in the laboratory. Every embryo usually hatches after it has reached the blastocyst stage. Good quality embryos reach this point usually on day five after fertilization, though some may take until day six. We routinely perform embryo transfers on the third day. In select cases, we will culture embryos to blastocyst stage before transferring them into the uterus.

Blastocyst transfers can increase the chance of pregnancy per embryo, while decreasing the risk of multiple pregnancies. We may find that only one blastocyst need be transferred in order to achieve an acceptable pregnancy rate. However, we also anticipate that individual clinical circumstances may lead us to recommend transfer of more than two blastocysts. Therefore, the final decision regarding the number of embryos transferred will remain a joint decision between the patient and physician on the day of transfer.