In vitro fertilisation (IVF) is a process in which the male partner’s sperm fertilises the female’s eggs in a lab, rather than inside the female’s body. The resulting organism is referred to as an embryo. Cryopreserved (frozen) embryos or fresh embryos can be used for IVF. Is one better than the other?
Some fertility centers are reporting slightly higher success rates with frozen embryos, including Fertility Centers of New England, which note that “Many patients are surprised that the frozen embryo transfer rates are equal to or higher than fresh embryo transfers.”
The Colorado Center for Reproductive Medicine (CCRM) believes there is an advantage to using frozen embryos. “In concordance with research at CCRM, studies from around the world have shown that in vitro fertilization pregnancies following a frozen embryo transfer are more similar to natural conception pregnancies than fresh embryo transfer cycles.” William Schoolcraft MD, medical director of CCRM says: “Since frozen embryo transfers occur a significant amount of time after a woman’s ovaries were stimulated with medications, the hormone levels in the body have had time to return to normal, which mimics a more natural conception process.”
According to Dr. Geoff Sher of Sher Fertility, a network of American fertility clinics, three developments have helped to improve the results achieved with frozen embryos:
While some IVF doctors state a preference for frozen embryos, the selection of frozen over fresh (or vice versa) will depend on a couple’s specific case and preferences. Fertility specialists can explain the IVF process using both fresh and frozen embryos and help patients determine which option suits them best.