Louise Brown, the first 'test tube baby,' is 45. Here's how IVF has changed since then.

On July 25, 1978, the world's first "test tube baby" was born. Louise Brown was the first person conceived through in vitro fertilization (IVF) and her birth eventually led to one of her doctors receiving a Nobel Prize.

Brown's birth got a lot of attention from around the world. Her mother's medical team filmed her caesarean birth to prove that she was, in fact, born from her mom, and photos of Brown were later released to help show the world that it was possible to have a healthy, normal baby through this new procedure. But her birth also raised a lot of questions about ethics and what IVF would mean for the future of humanity and procreation.

Brown's birthday — she turned 45 this year — is now known as World IVF Day. “Not long before mum passed away, she said that without IVF she wouldn’t have anybody left in the world,” Brown previously told Time. “Even up to her last days, she was proud of who she was and what she did.”

A lot has changed with IVF since its inception. Here's where things stand right now — and how far they've come.

The term "test tube baby" isn't used anymore.

Louise Brown was often referred to as a "test tube baby" because her conception started in a lab. "But there were no test tubes used — it was a petri dish," Dr. Jane Frederick, a board-certified reproductive endocrinologist at HRC Fertility, tells Yahoo Life.

As IVF has evolved and become more common, so has the language used to describe it, Dr. Thomas L. Toth, a reproductive endocrinologist with Boston IVF, says. "The terminology has changed as more sophisticated and more efficient techniques have developed in the lab to replace the early use of 'test tube baby,'" he says.

The term is also "outdated" and "could be considered offensive," Dr. Asima Ahmad, chief medical officer and co-founder of Carrot Fertility, tells Yahoo Life. "I do not recommend using this term," she says. "All pregnancies, whether as a result of fertility treatment or not, should be referred to with respect, regardless of how fertilization took place."

IVF success rates have improved.

Experts say that it's difficult to pin down exact numbers of IVF success rates, given that factors like the age of the parents and whether the mother has any underling health conditions can play a role. However, data from the Centers for Disease Control and Prevention (CDC) now show that IVF in the U.S. has a success rate of about 38% overall.

"I remember when a 10% success rate was respectable," Dr. James Grifo, a reproductive endocrinologist and director of the NYU Langone Fertility Center, tells Yahoo Life.

Overall, success rates really depend on the person, he says. "Now, we have implantation rates as high as 70% in certain populations and, with cumulative attempts, you can get most people pregnant," Grifo notes.

IVF has become much more common.

About 4 million births a year in the U.S. — or up to 2% of annual births — are due to IVF, the CDC reports. The Society for Assisted Reproductive Technology (SART) notes that less than 5% of assisted reproductive treatments are due to IVF.

"In the beginning, IVF was very controversial and misunderstood," Grifo says. "It wasn't very successful and it was a lot more invasive and complicated."

But Grifo says that things have "dramatically changed" since 1978. "The technology has improved dramatically and we're now better at finding the one good embryo that can make a baby," he says.

Some insurance companies and employers now cover IVF costs.

This has been huge for many families, Toth says. "Historically IVF was self-pay for those few who could afford such care," he says. "However, over time a growing number of states and companies recognized infertility as a disease and provided coverage for treatment for family-building as a needed medical treatment."

By insurance companies and employers covering IVF "it validates that infertility is a valid reason to seek a specialist. It's not just, 'You're infertile. We can't help you,'" Frederick says.

Genetic testing has been a game-changer for some families.

Preconception genetic screening and genetic testing for embryos has "revolutionized" the ability for parents to conceive a healthy baby, Toth says.

"Some couples have a gene that they carry, like for cystic fibrosis or Fragile X syndrome, and they want to avoid passing it on to their children," Frederick says. "It's now something we can test for to ensure a family has an unaffected embryo so their baby won't be born with certain conditions."

Grifo says genetic testing can also help doctors and families select the best embryos. "The thing that will get us the most success is to find the healthiest embryo," he says. "It's important to find those embryos."

Reasons families use IVF have expanded.

IVF used to meet a very specific need: It helped women suffering from infertility due to issues with their fallopian tubes, Dr. Zev Williams, a reproductive endocrinologist at Columbia University Fertility Center, tells Yahoo Life. By using IVF, doctors could bypass the fallopian tubes by retrieving the egg and fertilizing it in the lab, and then placing the fertilized egg into the uterus via the vagina and cervix.

"IVF has evolved tremendously in the past four decades," Williams says. "In addition to helping in cases of tubal factor, we can now help those suffering from male-factor infertility, uterine factor, unexplained infertility and those in the LGBTQ+ community." Egg and embryo freezing can also help people undergoing chemotherapy, as well as those who want to delay having kids or haven't yet found the right partner, he says.

"The use of donor egg, donor sperm and gestational carriers has further expanded the patients who can be helped," Williams says. "And now, with the advent of preimplantation genetic testing, we can help those who are carriers of some of the most devastating hereditary diseases go on to have children who are healthy and free of those diseases."

Experts say IVF has come so far since Brown's birth — and allowed for the creation of a range of families. "Sex ed makes it sound like it's so easy to get pregnant. It usually isn't," Grifo says.

This article was originally published on July 25, 2023 and has been updated.

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