Everything we know after ‘world’s oldest baby’ is born in the US

A baby boy was born last week and has immediately found himself in the record books for being the 'world's oldest baby'.

The birth of any baby is something to be celebrated, but the arrival of Thaddeus Daniel Pierce over the weekend was extra special for his parents, as science played a role in his successful birth.

Pierce was born on Saturday (26 July) to Lindsey and Tim Pierce, from Ohio, US, with his mom describing his birth as 'rough'.

"He is so chill. We are in awe that we have this precious baby!" she told MIT Technology Review.

While that all sounds pretty standard, how he came to be will be an interesting story, however - something of which Lindsey has compared to 'a sci-fi movie'.

So, what exactly makes his entrance into the world so extraordinary?

Who is the 'world’s oldest baby'?

Thaddeus Pierce was born on 26 July (Lindsey and Tim Pierce/Rejoice Fertility Clinic)

Thaddeus came from a batch of fertilised embryos originating from Linda Archerd, 62. Linda and her now ex-husband created a bunch of embryos back in 1994, one of which became their now 30-year-old daughter.

However, following her divorce, she had three embryos left over and initially had plans to use them for future children, however, this didn't happen.

So she decided to donate them to the Snowflakes program run by the Nightlight Christian Adoptions agency to help couples who are experiencing fertility problems, or for research purposes, with one of Linda's embryos being 'matched' to Lindsey and Tim.

After Thaddeus's birth, Linda said: “The first thing that I noticed when Lindsey sent me his pictures is how much he looks like my daughter when she was a baby.

"I pulled out my baby book and compared them side by side, and there is no doubt that they are siblings.”

Who are the 'world’s oldest baby’s' parents?

Lindsey and Tim Pierce had been trying to conceive for a long time (Lindsey and Tim Pierce/Rejoice Fertility Clinic)

Lindsey, 35, and Tim, 34, had been trying to conceive for seven years with no success when they decided to turn to an embryo adoption agency.

After donating her embryos, Linda, who is Christian, was allowed to specify any preferences regarding who she wanted her embryo to be donated to, and she said that she wanted her embryos to go to a married, white Christian couple living in the US, as she didn't want to 'go out of the country'.

The agency matched Lindsey and Tim with Linda, and two of the embryos were implanted into Lindsey's uterus in November 2024, with one developing into a fetus.

Lindsey told the MIT Technology Review of her happiness about their new arrival, saying that they didn't decide to go through with it 'thinking we would break any records', adding: “We just wanted to have a baby.”

How did the 'world’s oldest baby' break records?

Even though he is just a newborn, Thaddeus is the 'oldest' baby to be born because the embryo he came from had been frozen for more than 30 years.

Back in 2022, Rachel and Philip Ridgeway had twins from embryos which were frozen 30 years before, but Thaddeus has just pipped them to the post.

Lindsey described the whole thing as 'wild', adding: “We didn’t know they froze embryos that long ago.”

What are the challenges of using older embryos?

The embryo Thaddeus came from was frozen more than 30 years earlier (Getty Stock Images)

The method used to freeze embryos has changed significantly over the years thanks to advances in science and technology.

In the early days of IVF, embryos were slow frozen, which often caused ice crystals to form which could damage the embryo, and in the early 2000s, the process changed to one called vitrification.

According to IVI, this is an 'an ultra-rapid process', with embryos being lowered into tanks of liquid nitrogen. This process freezes the embryos much faster, turning them into a 'glass-like state'.

MIT says that some embryo agencies and fertility clinics won't accept older embryos as they are believed to be less likely to survive once they've been thawed out, and there can be complications with handling embryos frozen using the older methods.

Linda said that some of the places she'd spoken to 'wouldn’t even take my information'.

Executive director of the Snowflakes program which accepted her embryos, Beth Button, said: "I would say that over 90% of clinics in the US would not have accepted these embryos.”

After verifying Linda's medical records, her embryos went to the agency's 'Open Hearts' scheme, for 'hard to place' embryos, which Lindsey and Tim were signed up to.

How do embryo adoption agencies work?

There have been many technological advances when it comes to the IVF process (Getty Stock Images)

According to the BBC, embryo adoption is given as an option to couples struggling to conceive a child, which involves them receiving a donated embryo.

Some of these agencies have connections to religion, like Christianity.

The IVF clinic in Tennessee where the Pierce's had the embryos transferred is called Rejoice Fertility, who aim to transfer any embryo it received 'no matter the age or conditions'.

It is run by John Gordon, who is a reproductive endocrinologist and Reformed Presbyterian, and he says the clinic aims to reduce the number of embryos being held in storage.

He said (via The Guardian): “We have certain guiding principles, and they’re coming from our faith. Every embryo deserves a chance at life and that the only embryo that cannot result in a healthy baby is the embryo not given the opportunity to be transferred into a patient.”

While there are no exact figures on births resulting from embryo donation, it is certainly on the rise, with a 2023 study estimating that just under 2,500 embryo donations are performed per year in the US.