In October 2012, the American Society of Reproductive Medicine announced it no longer considers oocyte freezing experimental. Recent developments in preservation techniques mean that preserved eggs have better success rates than when slow-freezing techniques were used.
The American Society for Reproductive Medicine’s change, said Marcelle Cedars, MD, of the University of the California San Francisco, can be tied to positive research on vitrification, a fairly new form of oocyte preservation that improves blast development performance compared to slow-freezing methods.
“One of the things we worry about is that spindle upon which the chromosomes are aligned is interrupted in the process of freezing and thawing and then has to re-form,” said Marcelle Cedars. In studies, spindle abnormalities were no different in the control than in vitrification.
This raises complex questions for caregivers, Cedars said in a presentation at the Annual Congress of Obstetricians and Gynecologists Annual Meeting, like how they should counsel patients who wish to preserve eggs for social indications.
For many years, egg freezing was limited to women with cancer, when women no longer had the option to use fresh eggs.
In elective egg preservation for social indications, if studies indicate that it may take two or three cycles worth of eggs for a 35-year-old woman to achieve a live birth, what guidance do you give patients at 25, 30 or 35? Does a provider counsel a 35-year-old to harvest three cycles of eggs? Do they counsel women to preserve eggs at age 25 because the quality is higher and fewer eggs are needed?
“What if someone’s in a situation where she might otherwise have conceived, and she chose not to because she thinks she has this safety net,” Cedars said. “But if she doesn’t get pregnant with the cryo-preserved oocytes, they may be too old to try on their own.”
Cedars recommends cautioning women against using new ovarian reserve markers because it’s unknown whether they predict spontaneous pregnancies. But beyond that, she admits that she doesn’t have all the answers. Perhaps considering these questions is too paternalistic, she said. “Who is it for me to say if a patient wants to freeze her eggs. We have the capability to do it, maybe we should be doing it.”