Ovarian hyperstimulation syndrome, abbreviated OHSS, is an atypical reaction that women may experience in response to excessive hormones, and often occurs during fertility treatments. OHSS is typically triggered by hormonal medications designed to mature eggs in the ovaries, which can cause blood vessels within the ovaries to leak fluid. Sometimes that can lead to painful tenderness or swelling. In severe cases of OHSS, that fluid can leak into the abdominal cavity in large amounts, causing vomiting, blood clots, and severe pain. As many as one out of three women undergoing fertility treatment will experience some form of OHSS, although more severe presentations are rare. While the exact cause of OHSS is not fully understood as of 2020, researchers continue to discover various risk factors, prevention techniques, and treatments that may lead to decreased risks associated with OHSS and better fertility outcomes.

Alan Osborne Trounson is a scientist from Australia who studies embryology and stem cells. His research has improved the success rates of in vitro fertilization, or IVF. IVF is a medical procedure in which scientists fertilize an egg cell with sperm outside of the body, often in a laboratory petri dish, then transfer the fertilized egg to a woman’s uterus to start pregnancy. Trounson also researched embryonic stem cells, or stem cells collected from embryos, and their potential for treating injuries and diseases. Additionally, Trounson led the Californian Institute for Regenerative Medicine, or CIRM, one of the largest agencies to fund stem cell research in California, from 2007 to 2014. Over the course of his career, Trounson developed several techniques that improved the effectiveness of IVF, including fertility treatments and cryopreservation, and supported stem cell research as a scientist and administrator.