Angela Yu wants to be a mother, just not right now.
However, the 35-year-old Southern California neuroscientist and researcher is aware of an undeniable fact.
"I was looking at the reproductive biology of women and how that declines with age, and I got worried," Yu said, adding her love life isn't where she'd like it to be right now in order to have children.
She froze her unfertilized eggs this June. Her boyfriend was supportive; her parents weren't, even though they've wanted grandchildren from their only child for several years. "They went from hostile to the idea, to skeptical, to gradually accepting the idea," she said.
Part of their initial hostility, Yu said, stemmed from their unfamiliarity with vitrification, now the most common method used to freeze eggs.
Vitrification flash freezes eggs so quickly ice crystals can't form and damage cell membranes. It's slightly more effective and technically easier to do than the older method of slow freezing, which wasn't immune to ice crystallization.
Although vitrification has been around for more than a decade, it started grabbing more headlines last October when the American Society for Reproductive Medicine announced it should no longer be considered experimental because it's safe and effective.
A study published in 2010 and conducted by the New York University Fertility Center compared live birth rates achieved through egg freezing (using both vitrification and slow freezing) versus recent data of live births using fresh in vitro fertilized eggs (IVF.) Egg freezing yielded 57 percent compared to 60.4 percent for IVF.
"The likelihood of success [with egg freezing] is at best the same as the IVF likelihood of success at any given age," said Dr. Eve Feinberg, of the Fertility Centers of Illinois.
The ASRM's announcement has made vitrification an important part of the conversation for women considering the procedure, but its advocates say they must still overcome one large obstacle: Social stigma.
"Most women wouldn't feel any concern in talking in public about fertility using birth control or other forms of contraception, like there's not really any social stigma associated with that anymore, but there is with egg freezing," Yu said.
The stigma is closely associated with the image of a woman, unmarried and in her late 30s or early 40s, who turns to egg freezing as a desperate last resort to preserve her chance at hopefully one day getting pregnant.
Experts and those who have undergone the process say education is key to reframing this view, but it's also a means to combat the fact that many women are waiting too long to think about fertility.
In some cases they're missing the opportunity to have children or use egg freezing as a family planning method. Nearly one in five women in the United States doesn't bear a child, according to a 2010 Pew Research study.
"I'm not seeing the 30 and 31-year-olds who want to come in and preserve their fertility. I'm seeing the 39, 40, 41-year-olds, and so I think the message that's really important to get out is you're going to have the best likelihood of success if you freeze your eggs earlier," Feinberg said.
"It's a function of the age at which the eggs were frozen," that's the most important factor, not the age of the pregnant woman, said Dr. James Grifo, program director at the NYUFC.
So what's the best age for a woman to freeze her eggs?
"Probably optimally before 33, doable, you know, up to 40. Over 40 you're not looking at a very high chance," Grifo said.
That's something 40-year-old Brigitte Adams, who froze her eggs two years ago, said she wishes she had known, as her ovarian reserve was lower than average. For her this meant spending more money to mature enough viable eggs. "Take more ownership of your fertility and own it younger," Adams said. One way to do this is for women to request blood tests from their gynecologists to determine their ovarian reserves, a step she recommends for women in their early 30s.
It's unclear how many women have frozen their eggs for non-medical reasons because records aren't kept nationally, but at Grifo's clinic, 1,034 women had frozen their eggs as of December 2012. At two FCI clinics, 160 women froze their eggs from 2010 through 2012.
Research shows babies born from frozen eggs don't have a higher risk of birth defects. However, the data are limited and more research is necessary, according to the Mayo Clinic's website.
What various studies throughout the years do show is a woman's age at the time of pregnancy is a factor to consider. "We start to see increased complications with women who do become pregnant in their forties, but I think most fertility clinics and most high-risk obstetricians feel comfortable with women becoming pregnant well into their late forties," Feinberg said.
These complications include gestational diabetes, preeclampsia and an increased need for a C-section, among other difficulties.
Preparing eggs for vitrification involves about two weeks of daily hormone injections, as well as several blood tests and ultrasounds. Egg retrieval is usually done under anesthesia during a 15 to 20 minute in-patient procedure. Although rare, risks include ovarian hyper stimulation, which is painful swelling of the ovaries; infection; bleeding; and damage to the bladder, bowels or a blood vessel during the retrieval process, according to the Mayo Clinic website.
"We think that eggs are good for about 10 years. We don't have much data beyond that," Feinberg said.
For many, the biggest obstacle to egg freezing is its price tag, at anywhere from $10,000 to $15,000, or in some cases more. When done for elective purposes, it's not covered by insurance. And, even if more women jump on board, the price is likely to stay the same, Grifo said.
Nevertheless, those who opt for the procedure may feel the price point is reasonable.
"I thought it was a pretty inexpensive option to give you the option later in life to have children," said Amy Paris, a 39-year-old Chicago-area business owner who froze her eggs. However, experts like Grifo emphasize the importance of having realistic expectations. "Egg freezing is a hope. It's not a promise; it's not a guarantee."