Ovarian function and response to gonadotropins after prolonged perfusion of whole ewe ovaries in a bioreactor.

Summary: For young girls and women facing cancer treatments that damage fertility, options have been limited and risky. Current methods often involve removing ovarian tissue and transplanting it back later, but this carries a danger of reintroducing cancer cells hiding in the tissue.

In a breakthrough experiment, researchers successfully kept whole sheep ovaries alive outside the body using a specialized machine called a bioreactor. They tested different ways of feeding hormones to these ovaries. Surprisingly, they found that giving the ovaries a "rest" from hormones overnight worked better than constant stimulation. This "rest" protocol allowed the ovaries to produce mature eggs (oocytes) ready for fertilization. This marks the first time mature eggs have been harvested from whole ovaries kept alive this way, offering a promising, safer future path for preserving fertility without the risk of cancer recurrence.