- When kids of the future ask their parents how they were made, the response could go something like this: "Well, when two people love each other very much, they bring a tiny sample of their skin cells to a lab, turn those cells into sperm and eggs, then put them together to make a special baby, which turned into you."

That's a very basic explanation of a very real technique called in-vitro gametogenesis or IVG.

Scientists have already successfully done this procedure in mice, and humans are next.

And before you ask, no, sex isn't going away as the main method to make babies, but IVG has the potential to liberate reproduction from its biological limitations.

In the future, this technology could be transformative for people suffering from infertility.

And for same-sex couples, IVG can make it finely possible to have biological children that are related to both parents.

I'm Sinead Bovell.

Let's talk about the future of fertility.

[upbeat techno music] For millions of people, having biological children is incredibly difficult.

One in six people worldwide deal with infertility at some point in their life, and we still don't fully understand why.

The causes are complicated, ranging from problems with ovulation to low quality or abnormal sperm production.

But what we do know is the solutions can be very expensive and they often don't work.

The most common solution is in-vitro fertilization or IVF.

More than 40 years ago, the first IVF baby was born.

Her name is Louise Brown and her birth felt like a scientific miracle for parents who desperately wanted children, but who struggled with infertility.

This breakthrough didn't come without controversy.

The idea of scientists helping to create children in a lab was seen as highly unethical and it caused widespread outrage.

Thank goodness, scientists persevered.

Close to 2% of children born in the US are conceived through IVF.

But IVF has its downsides.

For starters, patients sometimes have to endure up to 90 injections of synthetic hormones in order to stimulate egg production.

And then they have to undergo an invasive procedure to harvest those eggs, which are then fertilized with sperm in a dish and reimplanted into the uterus.

It's an expensive and arduous process, and it's not always effective.

The success rate for patients under 35 is around 50%, but it shrinks to just 4% at 42 years old.

And as people are choosing to have children later in life, the need for more fertility solutions is growing.

For same-sex parents, there's an added complication to having kids.

There's always a third party involved, whether it's a sperm or an egg donor or a surrogate or an adoption agency.

And of course, there's the legal and financial hurdles that come with those options.

So what if we could bypass all of that?

What if all it took to have biological children was a few skin cells?

In 2006, scientists made a breakthrough that could make this possible.

Researchers discovered how to convert any cell, such as a skin cell or a blood cell, into what's called induced pluripotent stem cells.

Quick breakdown: Pluripotent means many potentials, so pluripotent stem cells are cells with the potential to become almost any cell in the body.

This unlocks a massive key to healthcare.

We can engineer someone's skin cells into new retinal cells if they are suffering from blindness.

Or turn somebody's blood cells into spinal cord cells to cure someone with paralysis.

Or we can turn skin cells into what will eventually become sperm or egg cells.

And scientists have already done this with mice.

They took skin cells from mice tails and were able to turn them into pluripotent stem cells.

From there, they engineered them into becoming gametes, the precursors of egg and sperm cells.

After incubating them in a Petri dish with the right hormones and compounds, they successfully created egg cells.

When the eggs matured, the team fertilized them with regular mice sperm and put them inside female mice.

A few weeks later, 10 mice pups were born.

They even went on to have babies of their own.

And even more incredibly, the same researchers took cells exclusively from male mice and created the first mouse offspring with two biologically male parents, opening the doors for fertility doctors to use any gender to create both egg and sperm cells.

Replicating this process in humans is the next step, but it won't be easy.

One of the biggest challenges is creating the perfect environment in a Petri dish; one that will encourage egg cells to mature normally.

And we don't actually know much about how this happens in the human body.

- We know very little about that, and we need those instructions of how the cells normally do it in the body.

We need to know what they are so that scientists are able to repeat those types of conditions and environments to make these cells become gametes outside of the body.

So while we don't know the instructions and the roadmap, it's very, very difficult to translate this technology from rodents to humans.

- This is Dr. Amander Clark, a stem cell scientist working on IVG.

Another problem she's worried about?

The health of babies conceived with IVG.

Cells could look healthy and functional in the lab, but turn out to have genetic errors that don't surface until the baby's born.

- The question is, are those changes too many or are they in places of the genome that could cause disease?

If either of those things happen, in-vitro gametogenesis will never make its way to be used for reproductive purposes.

- Despite those challenges, there are several startups working on IVG.

Their big focus is how do recreate a healthy environment for these cells outside the body; one that's capable of producing high-quality gametes.

If IVG works the way it should, it would mean an unlimited supply of embryos, and parents would've the ability to screen those embryos for genetic diseases and be given the chance to bring the healthiest baby into the world.

Let's assume we improve IVG technology and it is safe to use in humans.

We'd still need to contend with all the ethical issues, some of which we are familiar with.

For instance, the desire to create designer babies.

Access to lots of embryos could tempt some parents to genetically screen them for traits that aren't health related like height or IQ, which has some researchers worried.

- There's a real worry that this could sort of change our view of reproduction, that it sort of commodifies reproduction, that it pushes parents towards wanting the most perfect child possible.

- Sonia Suter is a legal and bioethics scholar, and she's been thinking a lot about how IVG will affect prenatal selection.

We also need to say that the science around genetically selecting desirable traits like height or eye color, it's incredibly dubious because genes don't always behave the way we think they will.

But you can see how this technology might be attractive to parents even if the results aren't foolproof.

Another problem, in 1996, the US Congress passed legislation that barred federal funding on embryo research.

So for now, all research on IVG will have to come from private companies, but eventually, there may be a patchwork of states in the US with different laws surrounding IVG.

- And so you could have this weird scenario that I've actually written about where you could, in some states, not be able to do any embryo research, but in other states, in theory, be able to do research on the embryo well into fetal development.

- Another pitfall is of course, access.

A single round of IVF can cost between 15 and $30,000: a price tag that's already out of reach for many families.

We don't know what IVG will cost, but it likely will be expensive, especially if you add in genetic screening technology.

- Wealthy families are likely to invest in these sorts of technologies to give their children an advantage and these companies that have profit incentives are gonna prey on that.

- And speaking of desirable genes, if IVG becomes a reality, what's to solve somebody from stealing a hair from Penelope Cruz or Timothée Chalamet to have their babies?

- I think in theory, that this could happen down the road and we would need stringent protections against that, but we shed DNA all the time.

It is a very hard thing to control and a very hard thing to police.

- I think the scientific community and the public need to decide what we want the future of IVG to look like.

But we also need to keep in mind that when IVF was first introduced to the world, there was a lot of pushback.

IVF was seen as commodifying human life and the idea of conception in a lab was viewed as wildly unethical along with lingering fears of a societal shift towards designer babies, yet thank goodness, scientists persevered.

2% of all babies in the US are born using IVF and there's widespread acceptance of the procedure for treating infertility.

Having children is a profound act of hope for a better future.

And if we can figure out the science and the ethics of IVG, it will only make that future more possible.

This technology has the potential to help so many people: from same-sex couples to people struggling with conception, to parents who have genetic diseases they don't wanna pass on to their children.

I think IVG will turn out to be one of the most important fertility technologies of our lifetime, and I'm so grateful to get a front row seat to this scientific breakthrough.

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