Transvaginal ultrasound-guided oocyte retrieval, also known as egg retrieval, is a surgical technique used by medical professionals to extract mature eggs directly from the women’s ovaries under the guidance of ultrasound imaging. In 1982, physicians Suzan Lenz and Jorgen Lauritsen at the University of Copenhagen in Copenhagen, Denmark, proposed the technology to improve the egg collection aspect of in vitro fertilization, or IVF. During IVF, a healthcare practitioner must remove mature eggs from a woman’s ovaries to fertilize them with sperm outside of the body. Transvaginal ultrasound-guided egg retrieval is a surgery that can be completed in a medical office setting in twenty minutes. Transvaginal ultrasound-guided egg retrieval increased mature egg collection and rates of successful fertilization, becoming the new standard for egg collection in IVF.

In 1983, researchers Alan Trounson and Linda Mohr published the article “Human Pregnancy Following Cryopreservation, Thawing and Transfer of an Eight-Cell Embryo,” hereafter “Human Pregnancy,” in the journal Nature. In the article, the authors describe an experiment that led to one of the world’s first pregnancies through cryopreservation, or freezing, of an eight-cell human embryo. They discuss an experiment conducted at the Monash University and Queen Victoria Medical Center in Melbourne, Australia. Prior to the article’s publication, scientists had reported on embryonic cryopreservation experiments with animals only. At the end of the article, the authors mention that the pregnancy ended in a spontaneous miscarriage due to problems unrelated to cryopreservation twenty-four weeks after embryonic transfer. Despite the miscarriage, “Human Pregnancy” is one of the first articles to describe a successful human pregnancy after cryopreservation, and demonstrated that cryopreservation, as part of in vitro fertilization treatment, was a viable option for humans as well.