It’s a Popular Procedure for Young Women to Consider Undergoing. I Hope They Understand What They’re Actually Buying.

Medical Examiner These Numbers Reveal the Truth About Freezing Your Eggs The procedure offers patients a real benefit—but maybe not the one you’d expect. Photo illustration by Slate. Photo by Samuel Corum/Getty Images. Sign up for the Slatest to get the most insightful analysis, criticism, and advice out there, delivered to your inbox daily. When Rep. Alexandria Ocasio-Cortez announced that she was freezing her eggs, two words stood out to me. “This is a choice that I am making to feel more in control of my life,” she said. The first word is “control”: Egg freezing has become culturally synonymous with controlling fertility and offering women agency. I get it. I am a woman around Ocasio-Cortez’s age, 36. I’m also a physician, trained in a profession that asks us to take action by identifying risk factors, diagnosing diseases, and intervening whenever possible. There is something appealing about applying this same approach to the biological clock. You might want kids, but you called it quits with your fiancé and the next few years at work are going to be pretty busy? Do something about it! But the second word that stood out to me in Ocasio-Cortez’s announcement is “feel.” She wants to feel more control. This is a savvy way to put it, and one that women considering freezing their eggs should pay attention to. Feeling control isn’t the same thing as having control, and it’s a distinction that we miss all too often when we talk about fertility preservation. The feeling of control that egg freezing offers is real. In one study of women who underwent egg freezing at the University of California, San Francisco, 88 percent described feeling more control over their reproductive planning thanks to the procedure. A similar percentage reported feeling happy they had frozen their eggs, even if they had not returned to use them. Simply having eggs stored away can offer peace of mind, even before we consider whether the eggs are ever used or how much actual control they end up offering. (The time period between when the women in this study froze their eggs and when they completed the survey was relatively short, a few to several years; the authors note that longer-term studies looking at satisfaction and regret are “greatly needed.”) In practice, most eggs never leave the cryotank. In one large study using national data from nearly 50,000 women who froze their eggs, fewer than 3 percent returned to use them during the study period. It’s possible that number would go up if the participants were surveyed again—the mean age at the time of egg freezing was 34.5, and the women were followed up with less than a decade later—but a single-digit return rate seems like a reasonable enough ballpark to discuss with women considering the procedure. What can happen that deters women from getting those eggs out of storage? Some may find a partner and conceive on their own; some may decide they no longer want children; and others may choose another path to parenthood, such as adoption. Whatever the reason, the overwhelming majority of eggs remain on ice. For the small minority of women who do return for their eggs, control remains elusive. A frozen egg is still several biological leaps away from a baby. The egg must survive thawing, then it must successfully be fertilized (even in a lab setting, this is not guaranteed to happen), then it must develop into an embryo. The embryo must successfully implant, and then even after implantation and a positive pregnancy test there’s risk of miscarriage. Attrition occurs at every step. Researchers at New York University who followed up with women 10 to 15 years after egg freezing found that, among those who returned to thaw their eggs, 77 percent were able to create an embryo, but only 31 percent ultimately had a child. More recent nationwide data put the live-birth rate at a similar 29 percent. Taking the eggs off ice, in other words, is far from taking home a baby. Women are born with all the eggs they will have, and freezing aims to preserve eggs when they are relatively young. But freezing eggs does not freeze in time the woman who may eventually carry a fetus that develops from one, or more, of them. A woman who freezes her eggs at 30 and uses them at 40 still experiences pregnancy at 40, with the higher risks of preeclampsia, gestational diabetes, and cesarean delivery that accompany advanced maternal age. Pregnancy and birth involve a level of ceding control for anyone who experiences them. A woman who has had time to become more established in her career, who has had time to find a supportive partner or otherwise surround herself with a community, may have more resources to mitigate this reality. But on a biological level, the loss of control that comes with bringing a baby into the world only intensifies later in life. It’s true that a woman who freezes her eggs and then decides to have a baby with them will have a biological advantage over the version of herself that did not undergo the procedure. But this advantage is an additional tool—not “control.” Few medical interventions truly “control” future outcomes. What makes egg freezing worthy of this scrutiny is the fact that it is an elective intervention that is expensive and invasive, and the outcome women ultimately care about is binary and profound: Will I have a child? It isn’t hard to understand why this promise of control is so appealing. We live in an era of hyper-quantification, with the ability to track everything from the number of steps we walk in a day to our heart rate to the hours spent in REM sleep. We’ve also been told we can have it all: carefully developed careers, balanced retirement accounts, a thriving social life in which plans actually make it out of the group chat—and, oh, by the way, fertility. The number of eggs you have stored can become another health metric to obsess over. But it’s also one that, as Ocasio-Cortez’s behind-the-scenes videos depict, is expensive, uncomfortable, and painful to pursue. Egg freezing does have value, and the psychological relief it can bring is real. But women who consider it deserve to understand what it is they are buying. Health Medicine Motherhood Pregnancy Women