The arc of a biological female’s life is often defined by milestones involving her uterus. A first period. A first pregnancy. A first birth. All of which lead up to the concluding event: menopause, the one-year timeframe after a menstrual cycle’s chaotic final run.
At birth, the average female ovary contains about 1 to 2 million eggs. After releasing all viable eggs, and without the ability to produce more during a lifetime, between the ages of 40 and 50 most women lose their ability to sexually reproduce. As a result, their monthly menstrual cycles end indefinitely. Ovaries atrophy and the hormones that stimulate the process, like estrogen, decline.
This can cause a flood of symptoms physically and emotionally, from hot flashes to anxiety to memory loss to dry skin and extreme mood changes. Menopause is a normal biological, albeit most times unpleasant, process that encapsulates two very taboo topics: female aging and female fertility. As a result, it’s been frequently treated as a disease and has been surrounded by shame. But what if we lived in a world where menopause could be delayed by decades, or even indefinitely?
You might be thinking, this sounds like the premise of Ann Patchet’s book “State of Wonder," in which a character searches for a drug that treats menopause. But in reality, doctors and scientists have been working toward this possibility since at least 1999. That’s when Dr. Kutluk Oktay, an ovarian biologist and director of the Laboratory of Molecular Reproduction and Fertility Preservation at Yale School of Medicine, performed the first ovarian transplant procedure with cryopreserved tissue in the world.
When a woman ovulates, only one mature egg is released, leaving many unused sitting on a top layer of the ovaries. In the process of ovarian tissue cryopreservation, doctors like Oktay remove that top layer, freeze it and store them for future use. Ovarian cryopreservation has become an effective option for women who have cancer when treatments, like chemotherapy, negatively impact the ovaries and can cause them to stop releasing eggs and estrogen. Oktay said hundreds of infants have been born from this procedure around the world. It’s no longer experimental.
“So, we started asking the question whether this could also be used for healthy women if they wanted to delay reproductive aging?” Oktay explained in an interview with Salon. “Once your eggs age, or you run out of eggs, you can’t get pregnant, nor are you producing hormones, so the procedure to freeze ovarian tissue preserves both.”
According to a recent study published in the American Journal of Obstetrics & Gynecology, co-authored by Oktay, new estimates suggest that for most healthy women under the age of 40, ovarian cryopreservation could delay menopause by decades. Precise estimates depend on when the ovarian tissue is harvested and replanted (an interactive calculator can provide more details for those who are curious), but for women under 30, according to the study, the procedure may be able to prevent menopause altogether. Oktay gave an example that if a woman has ovarian tissue frozen at age 28 and it's replanted at age 49 or 50, it could delay menopause by 50 years — potentially exceeding that person’s lifespan.
“The idea is that for many women, menopause is a rocky transition in their lives, and associated with many medical problems,” he said. “Freezing the tissue at a younger age, tapping into the surplus and returning it right before menopause, would enable them to delay that process.”
But does that mean we’d live in a world where 70-year-old women are having babies? While this has already happened with the help of in vitro fertilization (IVF), Oktay emphasized that the goal isn’t necessarily to enable women to have children into their 60s or 70s, but instead slow down the fertility aging process. As more women are having children later in life, and access to fertility treatment intersects with race and socioeconomic status, this could be another fertility option and perhaps make it more accessible. In part because this can be done in conjunction with another surgery, like an endometriosis surgery or cesarean section.
Plus, there are other barriers removed when it comes to ovarian cryopreservation. The process doesn’t require a patient to be ovulating, like egg freezing does, which means a patient doesn’t have to undergo hormone treatments. When it comes to potential health benefits, Oktay added there is research that suggests that women who experience menopause later in life — after the age of 55 — are less likely to have cardiovascular disease, bone loss, dementia, depression, anxiety or die early. Yet, delayed menopause has also been associated with an increased risk of endometrial and breast cancer.
But not everyone is convinced delaying menopause indefinitely is a good idea. Lynette Sievert, a biological anthropologist at UMass Amherst, told Salon one concern is that the risks associated with pregnancies, like preterm delivery, increase with age. If delaying menopause allows biological females to get pregnant later in life, these risks are bound to increase.
“You can say, ‘We're not going to have a menopause because we still have these viable eggs,’ but the risk of pregnancy is going to keep going up,” she said. “They haven't figured out a way to prevent that.”
She added that many evolutionary biologists believe in the grandmother hypothesis, which suggests that female humans evolved the menopause experience (which is not something all mammals do), so they can help out with their grandchildren later in life instead of being distracted by their own children. From that perspective, it’s better for natural selection for younger females to have children instead of older ones. “You end up with more genes in the next generation,” she explained.
But even if this becomes more common in the future, she’s not convinced it would totally remove the menopause from the human species in the future. Although it could be another option for fertility treatments, the current structure of the U.S. healthcare system inevitably restricts access to many.
“I can't imagine Medicare, for example, is ever going to say 'Okay, well, the 70 year old woman wants to have a baby now, so we're going to pay,'” she said. “So I don't think it's going to have a big evolutionary impact.”
Finally, there’s the concern that delaying menopause doesn’t guarantee a woman won’t experience menopausal symptoms, which Sievert said is one of the most stigmatized aspects of menopause. As one study noted, advances need to be made in the process as the science on eliminating menopause symptoms despite a delay is limited.
“If there aren’t any eggs left by the time she's 50, they're not going to be producing much in the way of estrogens, so she will still have an increased risk of osteoporosis,” Sievert said. “She will still have vaginal dryness, she will still have skin changes, she will still have all of these sorts of aging things that go along with a decline in estrogen — saving those eggs isn't going to make any difference.”
