Technology is Redefining the Age of 'Older Mothers'
Scientists are working on technologies that would enable more 70-year-old women to have babies.
In October 2021, a woman from Gujarat, India, stunned the world when it was revealed she had her first child through in vitro fertilization (IVF) at age 70. She had actually been preceded by a compatriot of hers who, two years before, gave birth to twins at the age of 73, again with the help of IVF treatment. The oldest known mother to conceive naturally lived in the UK; in 1997, Dawn Brooke conceived a son at age 59.
These women may seem extreme outliers, almost freaks of nature; in the US, for example, the average age of first-time mothers is 26. A few decades from now, though, the sight of 70-year-old first-time mothers may not even raise eyebrows, say futurists.
“We could absolutely have more 70-year-old mothers because we are learning how to regulate the aging process better,” says Andrew Hessel, a microbiologist and geneticist, who cowrote "The Genesis Machine," a book about “rewriting life in the age of synthetic biology,” with Amy Webb, the futurist who recently wondered why 70-year-old women shouldn’t give birth.
Technically, we're already doing this, says Hessel, pointing to a technique known as in vitro gametogenesis (IVG). IVG refers to turning adult cells into sperm or egg cells. “You can think of it as the upgrade to IVF,” Hessel says. These vanguard stem cell research technologies can take even skin cells and turn them into induced pluripotent stem cells (iPSCs), which are basically master cells capable of maturing into any human cell, be it kidney cells, liver cells, brain cells or gametes, aka eggs and sperm, says Henry T. “Hank” Greely, a Stanford law professor who specializes in ethical, legal, and social issues in biosciences.
Mothers over 70 will be a minor blip, statistically speaking, Greely predicts.
In 2016, Greely wrote "The End of Sex," a book in which he described the science of making gametes out of iPSCs in detail. Greely says science will indeed enable us to see 70-year-old new mums fraternize with mothers several decades younger at kindergartens in the (not far) future. And it won’t be that big of a deal.
“An awful lot of children all around the world have been raised by grandmothers for millennia. To have 70-year-olds and 30-year-olds mingling in maternal roles is not new,” he says. That said, he doubts that many women will want to have a baby in the eighth decade of their life, even if science allows it. “Having a baby and raising a child is hard work. Even if 1% of all mothers are over 65, they aren’t going to change the world,” Greely says. Mothers over 70 will be a minor blip, statistically speaking, he predicts. But one thing is certain: the technology is here.
And more technologies for the same purpose could be on the way. In March 2021, researchers from Monash University in Melbourne, Australia, published research in Nature, where they successfully reprogrammed skin cells into a three-dimensional cellular structure that was morphologically and molecularly similar to a human embryo–the iBlastoid. In compliance with Australian law and international guidelines referencing the “primitive streak rule," which bans the use of embryos older than 14 days in scientific research, Monash scientists stopped growing their iBlastoids in vitro on day 11.
“The research was both cutting-edge and controversial, because it essentially created a new human life, not for the purpose of a patient who's wanting to conceive, but for basic research,” says Lindsay Wu, a senior lecturer in the School of Medical Sciences at the University of New South Wales (UNSW), in Kensington, Australia. If you really want to make sure what you are breeding is an embryo, you need to let it develop into a viable baby. “This is the real proof in the pudding,'' says Wu, who runs UNSW’s Laboratory for Ageing Research. Then you get to a stage where you decide for ethical purposes you have to abort it. “Fiddling here a bit too much?” he asks. Wu believes there are other approaches to tackling declining fertility due to older age that are less morally troubling.
He is actually working on them. Why would it be that women, who are at peak physical health in almost every other regard, in their mid- to late- thirties, have problems conceiving, asked Wu and his team in a research paper published in 2020 in Cell Reports. The simple answer is the egg cell. An average girl in puberty has between 300,000 and 400,000 eggs, while at around age 37, the same woman has only 25,000 eggs left. Things only go downhill from there. So, what torments the egg cells?
The UNSW team found that the levels of key molecules called NAD+ precursors, which are essential to the metabolism and genome stability of egg cells, decline with age. The team proceeded to add these vitamin-like substances back into the drinking water of reproductively aged, infertile lab mice, which then had babies.
“It's an important proof of concept,” says Wu. He is investigating how safe it is to replicate the experiment with humans in two ongoing studies. The ultimate goal is to restore the quality of egg cells that are left in patients in their late 30s and early- to mid-40s, says Wu. He sees the goal of getting pregnant for this age group as less ethically troubling, compared to 70-year-olds.
But what is ethical, anyway? “It is a tricky word,” says Hessel. He differentiates between ethics, which represent a personal position and may, thus, be more transient, and morality, longer lasting principles embraced across society such as, “Thou shalt not kill.” Unprecedented advances often bring out fear and antagonism until time passes and they just become…ordinary. When IVF pioneer Landrum Shettles tried to perform IVF in 1973, the chairman of Columbia’s College of Physicians and Surgeons interdicted the procedure at the last moment. Almost all countries in the world have IVF clinics today, and the global IVF services market is clearly a growth industry.
Besides, you don’t have a baby at 70 by accident: you really want it, Greely and Hessel agree. And by that age, mothers may be wiser and more financially secure, Hessel says (though he is quick to add that even the pregnancy of his own wife, who had her child at 40, was a high-risk one).
As a research question, figuring out whether older mothers are better than younger ones and vice-versa entails too many confounding variables, says Greely. And why should we focus on who’s the better mother anyway? “We've had 70-year-old and 80-year-old fathers forever–why should people have that much trouble getting used to mothers doing the same?” Greely wonders. For some women having a child at an old(er) age would be comforting; maybe that’s what matters.
And the technology to enable older women to have children is already here or coming very soon. That, perhaps, matters even more. Researchers have already created mice–and their offspring–entirely from scratch in the lab. “Doing this to produce human eggs is similar," says Hessel. "It is harder to collect tissues, and the inducing cocktails are different, but steady advances are being made." He predicts that the demand for fertility treatments will keep financing research and development in the area. He says that big leaps will be made if ethical concerns don’t block them: it is not far-fetched to believe that the first baby produced from lab-grown eggs will be born within the next decade.
In an op-ed in 2020 with Stat, Greely argued that we’ve already overcome the technical barrier for human cloning, but no one's really talking about it. Likewise, scientists are also working on enabling 70-year-old women to have babies, says Hessel, but most commentators are keeping really quiet about it. At least so far.
Scientists Attempt to Make Human Cells Resistant to Coronaviruses and Ebola
Scientists are experimenting with turning certain genes on and off to make cells better fight viral infection.
Under the electronic microscope, the Ebola particles looked like tiny round bubbles floating inside human cells. Except these Ebola particles couldn't get free from their confinement.
They were trapped inside their bubbles, unable to release their RNA into the human cells to start replicating. These cells stopped the Ebola infection. And they did it on their own, without any medications, albeit in a petri dish of immunologist Adam Lacy-Hulbert. He studies how cells fight infections at the Benaroya Research Institute in Seattle, Washington.
These weren't just any ordinary human cells. They had a specific gene turned on—namely CD74, which typically wouldn't be on. Lacy-Hulbert's team was experimenting with turning various genes on and off to see what made cells fight viral infections better. One particular form of the CD74 gene did the trick. Normally, the Ebola particles would use the cells' own proteases—enzymes that are often called "molecular scissors" because they slice proteins—to cut the bubbles open. But CD74 produced a protein that blocked the scissors from cutting the bubbles, leaving Ebola trapped.
"When that gene turns on, it makes the protein that interferes with Ebola replication," Lacy-Hulbert says. "The protein binds to those molecular scissors and stops them from working." Even better, the protein interfered with coronaviruses too, including SARS-CoV-2, as the team published in the journal Science.
This begs the question: If one can turn on cells' viral resistance in a lab, can this be done in a human body so we that we can better fight Ebola, coronaviruses and other viral scourges?
Recent research indeed shows that our ability to fight viral infections is written in our genes. Genetic variability is at least one reason why some coronavirus-infected people don't develop symptoms while others stay on ventilators for weeks—often due to the aberrant response of their immune system, which went on overdrive to kill the pathogen. But if cells activate certain genes early in the infection, they might successfully stop viruses from replicating before the immune system spirals out of control.
"If my father who is 70 years old tests positive, I would recommend he takes interferon as early as possible."
When we talk about fighting infections, we tend to think in terms of highly specialized immune system cells—B-cells that release antibodies and T-cells that stimulate inflammatory responses, says Lacy-Hulbert. But all other cells in the body have the ability to fight infections too via different means. When cells detect the presence of a pathogen, they release interferons—small protein molecules named so because they set off a genetic chain reaction that interferes with viral replication. These molecules work as alarm signals to other cells around them. The neighboring cells transduce these signals inside themselves and turn on genes responsible for cellular defenses.
"There are at least 300 to 400 genes that are stimulated by type I interferons," says professor Jean-Laurent Casanova at Rockefeller University.
Scientists don't yet know exactly what all of these genes do, but they change the molecular behavior of the cells. "The cells go into a dramatic change and start producing hundreds of proteins that interfere with viral replication on the inside," explains Qian Zhang, a researcher at Casanova's lab. "Some block the proteins the virus needs and some physically tether the virus."
Some cells produce only small amount of interferon, enough to alert their neighbors. Others, such microphages and monocytes, whose jobs are to detect foreign invaders, produce a lot, injecting interferons into the blood to sound the alarm throughout the body. "They are professional cells so their jobs [are] to detect a viral or bacterial infection," Zhang explains.
People with impaired interferon responses are more vulnerable to infections, including influenza and coronaviruses. In two recent studies published in the journal Science, Casanova, Zhang and their colleagues found that patients who lacked a certain type of interferon had more severe Covid-19 symptoms and some died from it. The team ran a genetic comparison of blood samples from patients hospitalized with severe coronavirus cases against those with the asymptomatic infections.
They found that people with severe disease had rare variants in the 13 genes responsible for interferon production. More than three percent of them had a genetic mutation resulting in non-functioning genes. And over ten percent had an autoimmune condition, in which misguided antibodies neutralized their interferons, dampening their bodies' defenses—and these patients were predominantly men. These discoveries help explain why some young and seemingly healthy individuals require life support, while others have mild symptoms or none. The findings also offer ways of stimulating cellular resistance.
A New Frontier in the Making
The idea of making human cells genetically resistant to infections—and possibly other stressors like cancer or aging—has been considered before. It is the concept behind the Genome Project-write or GP-write project, which aims to create "ultra-safe" versions of human cells that resist a variety of pathogens by way of "recoding" or rewriting the cells' genes.
To build proteins, cells use combinations of three DNA bases called codons to represent amino acids—the proteins' building blocks. But biologists find that many of the codons are redundant so if they were removed from all genes, the human cells would still make all their proteins. However, the viruses, whose genes would still include these eliminated redundant codons, would no longer successfully be able to replicate inside human cells.
In 2016, the GP-Write team successfully reduced the number of Escherichia coli's codons from 64 to 57. Recoding genes in all human cells would be harder, but some recoded cells may be transplanted into the body, says Harvard Medical School geneticist George Church, the GP-Write core founding member.
"You can recode a subset of the body, such as all of your blood," he says. "You can also grow an organ inside a recoded pig and transplant it."
Church adds that these methods are still in stages that are too early to help us with this pandemic.
LeapsMag exclusively interviewed Church in 2019 about his latest progress with DNA recoding:
The Push for Clinical Trials
In the meantime, interferons may prove an easier medicine. Lacy-Hulbert thinks that interferon gamma might play a role in activating the CD74 gene, which gums up the molecular scissors. There also may be other ways to activate that gene. "So we are now thinking, can we develop a drug that mimics that actual activity?" he says.
Some interferons are already manufactured and used for treating certain diseases, including multiple sclerosis. Theoretically, nothing prevents doctors from prescribing interferons to Covid patients, but it must be done in the early stages of infection—to stimulate genes that trigger cellular defenses before the virus invades too many cells and before the immune systems mobilizes its big guns.
"If my father who is 70 years old tests positive, I would recommend he takes interferon as early as possible," says Zhang. But to make it a mainstream practice, doctors need clear prescription guidelines. "What would really help doctors make these decisions is clinical trials," says Casanova, so that such guidelines can be established. "We are now starting to push for clinical trials," he adds.
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.
Thousands of Vaccine Volunteers Got a Dummy Shot. Should They Get the Real Deal Now?
If a treatment or prevention is known to work, it is considered unethical to withhold it from volunteers in order to prolong a research trial, experts say.
The highly anticipated rollout of a COVID-19 vaccine poses ethical considerations: When will trial volunteers who got a placebo be vaccinated? And how will this affect the data in those trials?
It's an issue that vaccine manufacturers and study investigators are wrestling with as the Food and Drug Administration is expected to grant emergency use authorization this weekend to a vaccine developed by Pfizer and the German company BioNTech. Another vaccine, produced by Moderna, is nearing approval in the United States.
The most vulnerable—health care workers and nursing home residents—are deemed eligible to receive the initial limited supply in accordance with priority recommendations from the Centers for Disease Control and Prevention (CDC).
With health care workers constituting an estimated 20 percent of trial participants, this question also comes to the fore: "Is it now ethically imperative that we offer them the vaccine, those who have had placebo?" says William Schaffner, an infectious diseases physician at Vanderbilt University and an adviser to the CDC's immunization practices committee.
When a "gold-standard" measure becomes available, participants in the placebo group "would ordinarily be notified" of the strong public health recommendation to opt for immunization, says Johan Bester, interim assistant dean for biomedical science education and director of bioethics at the University of Nevada, Las Vegas School of Medicine.
"If a treatment or prevention exists that we know works, it is unethical to withhold it from people who would benefit from it just to answer a research question." This moral principle poses a quandary for ethicists and physicians alike, as they ponder possible paths to proceed with vaccination amid ongoing trials. Rigorous trials are double-blinded—neither the participants nor the investigators know who received the actual vaccine and who got a dummy injection.
"The intent of these trials is to follow these folks for up to two years," says Marci Drees, infection prevention officer and hospital epidemiologist for ChristianaCare in Wilmington, Delaware. At a minimum, she adds, researchers would prefer to monitor participants for six months.
"You can still follow safety over a long-term period of time without actually continuing to have a placebo group for comparison."
But in the midst of a pandemic, that may not be feasible. Prolonged exposure to the highly contagious and lethal virus could have dire consequences.
To avoid compromising the integrity of the blinded data, "there are some potentially creative solutions," Drees says. For instance, trial participants could receive the opposite of what they initially got, whether it was the vaccine or the placebo.
One factor in this decision-making process depends on when a particular trial is slated to conclude. If that time is approaching, the risk of waiting would be lower than if the trial is only halfway in progress, says Eric Lofgren, an epidemiologist at Washington State University who has studied the impact of COVID-19 in jails and at in-person sporting events.
Sometimes a study concludes earlier than the projected completion date. "All clinical trials have a data and safety monitoring board that reviews the interim results," Lofgren says. The board may halt a trial after finding evidence of harm, or when a treatment or vaccine has proven to be "sufficiently good," rendering it unethical to deprive the placebo group of its benefits.
The initial months of a trial are most crucial for assessing a vaccine's safety. Differences between the trial groups would be illuminating if fewer individuals who got the active vaccine contracted the virus and developed symptoms when compared to the placebo recipients. After that point, in vaccine-administered participants, "you can still follow safety over a long-term period of time without actually continuing to have a placebo group for comparison," says Dial Hewlett Jr., medical director for disease control at the Westchester County Department of Health in New York.
Even outside of a trial, safety is paramount and any severe side effects that occur will be closely monitored and investigated through national reporting networks. For example, regulators in the U.K. are investigating several rare but serious allergic reactions to the Pfizer vaccine given on Tuesday. The FDA has asked Pfizer to track allergic reactions in its safety monitoring plan, and some experts are proposing that Pfizer conduct a separate study of the vaccine on people with a history of severe allergies.
As the FDA eventually grants authorization to multiple vaccines, more participants are likely to leave trials and opt to be vaccinated. It is important that enough participants choose to stay in ongoing trials, says Nicole Hassoun, professor of philosophy at the State University of New York at Binghamton, where she directs the Global Health Impact program to extend medical access to the poor.
She's hopeful that younger participants and individuals without underlying medical conditions will make that determination. But the departure of too many participants at high risk for the virus would make it more difficult to evaluate the vaccine's safety and efficacy in those populations, Hassoun says, while acknowledging, "We can't have the best of both worlds."
Once a safe and effective vaccine is approved in the United States, "it would not be ethically appropriate to do placebo trials to test new vaccines."
One solution would entail allowing health care workers to exit a trial after a vaccine is approved, even though this would result in "a conundrum when the next group of people are brought forward to get the vaccine—whether they're people age 65 and older or they're essential workers, or whoever they are," says Vanderbilt physician Schaffner, who is a former board member of the Infectious Diseases Society of America. "All of a sudden, you'll have an erosion of the volunteers who are in the trial."
For now, one way or another, experts agree that current and subsequent trials should proceed. There is a compelling reason to identify additional vaccines with potentially greater effectiveness but with fewer side effects or less complex delivery methods that don't require storage at extremely low temperatures.
"Continuing with existing vaccine trials and starting others remains important," says Nir Eyal, professor and director of Rutgers University's Center for Population-Level Bioethics in New Brunswick, New Jersey. "We still need to tell how much proven vaccines block infections and how long their duration lasts. And populations around the world need vaccines that are easier to store and deliver, or simply cheaper."
But once a safe and effective vaccine is approved in the United States, "it would not be ethically appropriate to do placebo trials to test new vaccines," says bioethicist Bester at the University of Nevada, Las Vegas School of Medicine. "One possibility if a new vaccine emerges, is to test it against existing vaccines."
In a letter sent to trial volunteers in November, Pfizer and BioNTech committed to establishing "a process that would allow interested participants in the placebo group who meet the eligibility criteria for early access in their country to 'cross-over' to the vaccine group." The trial plans to continue monitoring all subjects regardless of whether people in the placebo group cross over, Pfizer said in a presentation to the FDA today. After Pfizer has collected six months of safety data, in April 2021, it plans to ask the FDA for full approval of the vaccine.
In the meantime, the company pledged to update volunteers as they obtain more input from regulatory authorities. "Thank you again for making a difference by being a part of this study," they wrote. "It is only through the efforts of volunteers like you that reaching this important milestone and developing a potential vaccine against COVID-19 is possible."
CORRECTION: An earlier version of this article mistakenly stated that the FDA would be granting emergency "approval" to the Pfizer/BioNTech vaccine, rather than "emergency use authorization." We regret the error.