Live birth rates after IVF are lower with frozen donor eggs, study shows

The use of cryopreserved donor oocytes for in vitro fertilisation (IVF) is associated with lower live birth rates than those from fresh donor oocytes, US figures reported in a research letter to JAMA have shown.1

Donated oocytes’ use in IVF has increased dramatically in the United States in the past few years. Donated eggs were traditionally used immediately to create embryos, and any extra embryos left over from implantation were cryopreserved for later use. But some IVF centres have started to establish frozen donor egg banks after the American Society …