Freezing Embryos Doesn’t Boost IVF Success Rate Despite Common Use
June 25, 2019
(New Scientist) – A commonly used fertility medicine technique of freezing embryos and waiting several weeks before using them is ineffective at boosting pregnancy rates, a trial has shown. The approach is growing in popularity, and in the US about a quarter of IVF cycles now use this “freeze-all” strategy, although this includes women who need it for health reasons. During standard IVF, women take medicines to encourage their ovaries to produce several eggs, which are then collected and fertilised with sperm in a dish. Any embryos are allowed to grow for a few days before one or two are transferred into the uterus in the hope one will implant and lead to pregnancy. Any spare embryos are frozen for future attempts.