Research shows frozen human eggs are as effective as fresh eggs to preserve fertility

Fertility specialists responsible for the first pregnancy in the Pacific Northwest resulting from frozen human eggs are hailing new research showing that frozen eggs can be as effective as fresh eggs in helping previously infertile women achieve pregnancy.

Among new studies presented at the meeting of the American Society for Reproductive Medicine in October was one from Reproductive Biology Associates of Atlanta, finding that 85 percent of eggs survived thawing and that subsequent in vitro fertilization (IVF) of those eggs generated a 67-percent pregnancy rate—as good as the average success rate for fresh eggs. A second study from the New York University Fertility Center reported similar results in women who used frozen eggs to preserve fertility after cancer treatment.

"Until recently, egg freezing was largely reserved for women undergoing cancer treatment who set aside their eggs in hopes of preserving post-recovery fertility options," said Dr. Gerard Letterie, founder of Northwest Center for Reproductive Sciences (NCRS).  A long-time researcher on fertility preservation, Letterie said the option was almost non-existent before 2004. Today NCRS is among a small minority of practices capable of egg freezing, thawing and fertilization.  

Traditional egg freezing causes harmful crystals to form on eggs, decreasing their viability. "The new studies reinforce our success with vitrification, a superior fast-freezing process," he said. "Now we can create fewer embryos on an as-needed basis, returning to storage for more later, rather than putting a patient through additional egg retrievals," he said.

Improved freezing allows women to postpone pregnancy, whether due to medical necessity, career demands, lack of a partner, or ethical concerns. Letterie said more single women, pressured to find a perfect partner, are freezing their eggs to guarantee their chances of having their own biological children when they find their desired partner or begin their families as single mothers by choice.