A clear blob floats on a tray below the microscope, its image projected onto a screen. A tool that on the screen resembles a glass straw, manipulated by the specialist looking into the eyepiece, approaches the blob and tugs at a small piece of it. A laser beam severs the piece, and the pipette sucks it in.
The blob is a human embryo, invisible to the naked eye, now destined for freezing at Brigham and Women’s Hospital’s IVF clinic. Meanwhile, the five or six cells in the pipette will be sent for genetic testing.
This procedure is one of the reasons why women today — those who can afford it — can have higher hopes that a baby will result from in vitro fertilization: Fertility doctors have improved their ability to select embryos that will survive in the uterus.
As the Alabama Supreme Court ruling casts a spotlight on infertility treatment, two striking facts stand out. One is the increase in success rates, known as the “take-home baby” rate. The other is the reality that many women still go through the grueling IVF process without ever bringing home a baby. But that fact has not stopped the growth of the IVF industry, which is projected to reach $13.2 billion by 2030.
According to data collected by the CDC, when an embryo created by IVF is transferred to a woman’s uterus, a baby results only a quarter to a third of the time, even at the highest quality centers. (That’s up from around 10 percent in 1985.) But the odds vary tremendously depending on the woman’s age and health, and how many times she goes through an IVF cycle. The chances may be low with just one try, but women who go through multiple cycles increase the likelihood of eventually getting a baby.
Because most women up their chances by having embryos transferred multiple times, “As it currently stands, about 75 to 80 percent of all women who walk into the doors of Boston IVF walk out with a baby,” said Dr. Denis Vaughan, a reproductive endocrinologist who is Boston IVF’s research director.
And if the woman is willing to keep trying with multiple cycles, the success rate can reach 90 percent to 95 percent, said Dr. Antonio Rosario Gargiulo, a reproductive endocrinologist and surgeon at Brigham and Women’s Hospital.
The insurance coverage for infertility — mandated by a Massachusetts state law that doesn’t apply to every insurance plan — is a key reason why IVF is a big industry here. In 2021, 5.4 percent of Massachusetts births resulted from IVF, the highest percentage in the nation, according to the CDC. The national average is 2.3 percent. But because the law doesn’t apply to most insurance plans offered by large employers, Vaughan estimates that only about 45 percent of Massachusetts residents have this coverage.
Alexa Nicholls Costa is coming up on 38 weeks in her pregnancy facilitated by IVF.
Still working full time as a nurse practitioner at her Charlestown cosmetic dermatology practice, she feels thankful for her care at Boston IVF, her insurance benefits, and the support she’s received from family and friends — all of which have helped make her IVF process relatively smooth.
Costa, 35, had her first son, who is now 3 years old, “the conventional way,” she said. But when she was 12 weeks pregnant with him, she learned she was at high risk for carrying a genetic condition, leading to a stressful span of genetic testing and anxious waiting to make sure she and her baby were healthy.
They were found to be fine, but after that experience, Costa decided to opt for IVF for her next pregnancy; it offered a way to ensure her embryo was healthy without the stress and uncertainty of genetic testing of the fetus, which she said felt “invasive.” With IVF, an embryo can be tested, rather than the fetus.
“Being five months pregnant and waiting for genetic testing to come back feels pretty cruel,” Costa said. “I wouldn’t want to go about it that way again.”
IVF was important for Costa’s pregnancy for another reason: During the genetic screening process she went through with her last pregnancy, she learned that her ovarian function was diminishing. The two IVF cycles she endured then provided a more reliable way to produce a healthy embryo that might not have been possible otherwise.
Although her own process was “relatively straightforward,” Costa knows that’s not the case for everyone.
Costa’s cousin, Marisa Penta, 30, a psychologist in Revere, said her own experience with IVF has been an “emotional rollercoaster.”
It took two and a half years of trying before Penta became pregnant. Her journey was a series of jumps among insurance plans, fertility clinics, and varying degrees of hope and disappointment.
Penta and her wife initially were required by their insurance to attempt intrauterine insemination, in which sperm is inserted directly into the uterus, six times before they could receive access to IVF. The procedures were paid for out-of-pocket by the couple.
Now, after a change in their insurance gave the couple unfettered access to IVF, Penta is 24 weeks into a healthy pregnancy. But the measures it took to get there, she said, were “emotionally taxing.”
”We were having to go through heartbreak after heartbreak, month after month, before we could even do IVF,” Penta said. “Because of insurance restrictions.”
Eight companies, some with multiple locations, offer IVF services in Massachusetts. They include Massachusetts General Hospital, the Brigham, and Boston IVF, the largest IVF center in the country.
As more couples struggle with infertility — because of delayed child-bearing, health issues such as obesity, and possibly a decline in sperm counts — IVF has become a booming business. In the United States it is projected to grow from $7.5 billion in 2022 to $13.2 billion by 2030, according to Insights10, a health care-focused market research firm. The number of infants born as a result of IVF increased by 33 percent from 65,000 in 2012 to 97,000 in 2021, according to the CDC.
One IVF cycle, which involves hormones to stimulate ovulation, harvesting of eggs, fertilization in the laboratory, and transferring an embryo to the uterus, costs about $20,000, but medications and genetic testing can boost the price, and many women go through more than one cycle and end up spending in the six figures.
Women endure this ordeal because they yearn for a child, but also because they have reason for hope, especially if they’re under 35. For that age group, about half of IVF cycles lead to a live birth, and if a woman goes through three to five cycles her odds can increase to 90 percent or higher. Older women have a much harder time. For people over 42, one IVF cycle produces a baby only 2 or 3 percent of the time.
The growing success rate results not from a single dramatic discovery but rather the fine-tuning of procedures over the years, according to Boston infertility doctors.
Doctors have gotten better at growing embryos. They’ve figured out the ideal makeup of the fluid where the microscopic blobs float, the temperature in the room, the methods for freezing and thawing embryos, and even the composition of the air in the clinic. It used to be that many embryos would die after a day or two, but now they can grow for several days, so that more robust embryos can be transferred, Vaughan said.
But one of the biggest advances of the past decade is the screening for chromosomal abnormalities. This service isn’t covered by insurance, even in Massachusetts, but for older women the extra $5,000 to $10,000 may be worth it. As women age, the number and quality of their eggs decline. Conditions involving extra or missing DNA are a key reason why the embryo fails to implant in the uterus in older women. About half the embryos at Boston IVF undergo genetic testing, and about 35 percent at the Brigham.
“In a 23-year-old, almost all embryos are normal. In a 43-year-old, almost no embryos are normal,” Gargiulo said. “So obviously, you have to do more cycles.” But if a 43-year-old does produce a chromosomally normal embryo, she has the same chance of success as a 23-year-old, he said.
The enhanced ability to select embryos has also prevented one of the more serious problems that previously dogged IVF — multiple births. Years ago, doctors would transfer several embryos in the hope that one would implant, but sometimes three or four took root, putting the mother and children at great risk. Now it’s standard practice to insert only one embryo each cycle, and even twin births are rare.
Another big improvement has been the use of frozen embryos. Preserving the embryos for another date gives a woman’s uterus time to clear the hormones used to stimulate ovulation and return to a more normal, receptive state. By 2020, frozen embryos were used two-thirds of the time, up from under 5 percent in 2004. Some IVF clinics will only work with frozen embryos.
For the future, fertility researchers are exploring methods of extracting DNA from the fluid around the embryo, so genetic testing can be performed without cutting into the embryo. Also under study: the use of artificial intelligence to aid in sperm and embryo selection, and time-lapse photography to watch an embryo’s growth without disturbing it.
But after the exponential leap over the past decade, the success rates may be starting to plateau. “We don’t know what the next big thing is that is going to give us 5, 10, 15 percent [improvement],” said Dr. Pietro Bortoletto, a reproductive endocrinologist and the director of reproductive surgery at Boston IVF. “Now we’re fighting for single digit improvements.”
The biggest challenge is the persistent mystery of the uterus. What enables an embryo to implant in the uterus, and what prevents it? Even more perplexing, why doesn’t a woman’s immune system reject the fetus as a foreign object? Could a dysfunction in that process have a role in infertility?
“It’s in vitro fertilization; there is no in vitro implantation,” Gargiulo said. “And the birth process is mostly about implantation. And that part, it’s unfortunately up to nature.”
Forty-six years after the first “test-tube baby” was born in England, infertility treatments have improved greatly, but doctors are not close to 100 percent success with IVF, said Gargiulo. “We probably never will be,” he said.
Globe correspondent Maddie Khaw contributed to this report.
Felice J. Freyer can be reached at felice.freyer@globe.com. Follow her @felicejfreyer.