On July 25, 1978, the way the world views infertility changed dramatically.

On that day, Louise Brown, dubbed the world’s first “test tube baby,” was born.

Today, reproductive science has advanced significantly. We have egg donors and paid surrogates. On the horizon is a device akin to an artificial womb.

To sort out the technology and its implications, we turned to Margaret Marsh and Wanda Ronner. Sisters in real life, they have also been called “the infertility sisters” by those who know their writing on the issue. Marsh is a professor of history at Rutgers University, working in Camden and New Brunswick. Ronner is a professor of clinical obstetrics and gynecology at the University of Pennsylvania’s Perelman School of Medicine.

They spoke to us recently about their new book, The Pursuit of Parenthood: Reproductive Technology from Test-Tube Babies to Uterus Transplants.

What are assisted reproductive technologies and when did they become available?

MARSH: Sometimes people think that assisted reproductive technology is all infertility treatment. Assisted reproductive technologies are ones in which eggs or embryos are handled outside the body. If you’re receiving a fertility drug to help you ovulate, that’s an infertility treatment, but not assisted reproductive technology.

The first baby in the world born as a result of assisted reproductive technology was Louise Brown. Her mother was a 30-year-old homemaker who had been trying to get pregnant since she was 18 or 19. She had tubal disease, so it was impossible for the egg and sperm to meet in the natural way.

And that was the beginning of what you might call the IVF revolution. Brown was born in England. The second country to have an IVF baby was Australia. During the 1970s, Americans weren’t doing research on IVF because there was a federal government moratorium on funding for it.

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RONNER: The first American baby was born in December 1981. Two prominent physicians — Georgeanna Jones and her husband, Howard Jones — were able to set up an IVF program at Eastern Virginia Medical School in Norfolk. But because this was an “unproven” medical treatment, the patients were the ones who had to pay.

That’s an important part of the story because it feeds into our notion of why we call the U.S. the Wild West of reproductive medicine. The research didn’t go through the channels that most medical research goes through before becoming a standard procedure in hospitals.

MARSH: This is also important because we’re talking about a very expensive technology — then and now. The first year their clinic was open, the Joneses waived their fees. But there were all these tests and other things that needed to be done. The patients were on the hook for about $4,000. This was at a time when the median income in the U.S. was around $21,000. Some people seeking treatment mortgaged their homes. If you had severe tubal disease — the condition that IVF was created to address — you were probably not going to be able to get pregnant any other way.

Then the technologies started to multiply?

RONNER: Then we had IVF with donor eggs, with donor sperm, with both. Two newer technologies involve diagnosing a disease in an embryo or screening its chromosomes. Then they don’t implant the embryo with, say, cystic fibrosis or the BRCA gene mutation for breast cancer.

MARSH: In the 1990s, they developed pretty much the first technology for severe male infertility. If a man has any normal sperm, his doctors can remove them and inject a single sperm into the woman’s egg.

Are IVF and other reproductive technologies regulated by the federal government?

MARSH: The short answer is no. There are some state laws having to do with gestational surrogacy, or who gets custody of frozen embryos if there’s a divorce. But they vary. One exception is a federal consumer protection law that requires IVF centers to report their success rates to the federal government. There’s no enforcement mechanism, but most clinics do it.

This is very different from almost every other developed country, which is another reason we’re called the Wild West of reproductive medicine. Great Britain, for example, has an independent, nonpartisan authority that is nongovernmental but is responsible for approving new technologies and regulating their use.

RONNER: My colleagues would say that we do a pretty good job of policing ourselves. I’m not so sure. The reproductive endocrinology community tries to follow professional guidelines, such as how many embryos do you insert at a time based on a patient’s age. They have done a good job reducing the higher order multiple births — triplets and higher.

We need more data to figure out what works the best for certain types of infertility. But even today, there’s an ongoing budget rider to the NIH appropriations bill that perpetuates the 1970s ban on federal funding of human IVF and human embryo research. It doesn’t mean research isn’t being done. But it’s not the same kind of peer-reviewed, NIH-funded research that occurs in every other specialty.

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You write that fertility care, including basic IVF, should be considered part of women’s basic health care and covered by insurance.

RONNER: We have a long history of ignoring the health-care needs of women, not only in providing routine prenatal care and routine gynecologic care. We believe that infertility care is part of the total health care of women. We not only want to help women who don’t want to become pregnant, we want to help women who cannot become pregnant because of infertility.

MARSH: There are only seven states that mandate more or less comprehensive insurance coverage for in vitro fertilization. New Jersey is one. Pennsylvania is not.

You also discuss whether there should be limits on assisted reproduction.

MARSH: Well, we raise these ethical questions. What kinds of technologies are ethical and what kinds might not be ethical? In the 1980s, a woman might show up with a sister or a friend who would donate an egg. Today, even though donors are compensated, it has been framed that the donor was giving a gift to another woman to allow her to have a baby. What happens to that idea when a clinic can buy sperm from a sperm bank, eggs from an egg bank, put them together and offer them pretty much for sale? That is what’s happening now in one fertility center.

RONNER: Another question is, do we get to a time in which a woman has reached the age limit beyond which she should not get pregnant? In this country, we have guidelines, but we also have women well past age 50 who are getting pregnant with donor eggs. Maybe we can revitalize the uterus at any age, but what about the rest of the body? There are health risks associated with women over age 50 becoming pregnant.

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There are also ethical questions around surrogacy. Many times, it’s a rich woman buying a poor woman’s uterus to have her baby. And there’s the potential health risk to the surrogate. Many countries ban paid surrogates.

MARSH: If you’re born with no uterus, or you’re a gay male couple, and you want to have a baby, the only way is if you have this gestational surrogate. I feel a lot of sympathy with these parents who otherwise would be unable to have a child genetically related to them. On the other hand, it’s hard to ignore stories of surrogates being exploited, or of babies born with birth defects that the genetic parents will not then accept.

RONNER: Now we have uterus transplantation, which is being researched at three centers in this country, including Penn. We’ll see how that goes. Before Louise Brown was born, the public didn’t believe IVF could happen. Here we are, shaking our heads about uterus transplants. But it’s worked. We have two babies born from uterus transplants in this country.

MARSH: If you want true futurism, researchers are developing what they call womb-like devices. They’re designed for extremely premature babies to help them survive better. But is this a step toward the external artificial uterus? Who knows?