美国国家公共电台 NPR Scientific Duo Gets Back To Basics To Make Childbirth Safer（在线收听）

DAVID GREENE, HOST:

This is the story about two women, a doctor and a mechanical engineer. They came together to study one of the most basic parts of human life - pregnancy and labor. That's because there's a lot we just don't know. NPR's Alison Kodjak reports on this unusual pair of researchers who are trying to learn more.

ALISON KODJAK, BYLINE: Dr. Joy Vink deals only with the hardest cases, cases like that of Brittney Crystal. Crystal was under Vink's care when she went into labor at just 28 weeks pregnant. She was rushed into an operating room at Columbia University Medical Center for an emergency C-section to try to save her baby, whom she had already named Iris.

BRITTNEY CRYSTAL: And I think I knew before I opened my eyes that she had died.

KODJAK: Afterward, as she was recovering in the hospital and mourning the loss of Iris, Crystal and her family asked Dr. Vink why there was no way to stop the premature labor.

CRYSTAL: And that's when Dr. Vink told us that actually, you know, rare diseases are being cured in this day and age, but we don't know what triggers full-term labor, which I think just collectively blew away everyone in the room.

KODJAK: Vink runs the Preterm Birth Prevention Center at Columbia. She says when it comes to pregnancy, basic research stalled decades ago. If a pregnancy is normal, that's not all that important. But when things go wrong, she says those gaps in knowledge become issues of life and death.

JOY-SARAH VINK: It's heartbreaking. It's heartbreaking to see patients who, either on their first or on their third, fourth, fifth time around, are losing a pregnancy right at that cusp of viability.

KODJAK: Crystal had what was called a short cervix, which put her at risk for going into labor early. She'd had a procedure called a cerclage, which is basically a stitch in her cervix to keep it closed and prevent an early birth. The technique has been around for more than 50 years. And while there's research to show it may help, the information is limited. Most of the basic knowledge about pregnancy comes from research performed in the 1940s, so Vink decided this time to learn more. She's starting by getting to know the cervix.

VINK: So what is the cervix made out of? What proteins are there? What cells are there? How are all these things interacting? How go they change in pregnancy? How does the cervix go from a stiff, sort of strong structure that's like the consistency of the tip of your nose to something that's as soft as butter by the end of pregnancy?

KODJAK: Her lab is full of graduate students.

VINK: We actually are taking tissue samples from the cervix from non-pregnant women as well as in pregnancy to understand what is a tissue made out of.

KODJAK: And while she's figuring out what it's made out of, she's teamed up with someone who can figure out what it can do - Kristin Myers.

KRISTIN MYERS: I'm kind of a oddball here in the Department of Obstetrics and Gynecology. I'm a mechanics person. I teach mechanics classes and design classes.

KODJAK: Myers got her start doing undergraduate research in the automobile industry looking at how rubber and tires degrades.

MYERS: So if you take rubber, and you heat it up, and you pull on it, it gets really, really soft. And then it breaks.

KODJAK: Her advisor suggested she could apply that kind of research to biology. And when she got to graduate school at MIT, she met Michael House, who was studying the biomechanics of pregnancy.

MICHAEL HOUSE: It's an important area, an understudied area and a basic part of pregnancy physiology. And I think that there's just lots to learn.

KODJAK: House, who's at Tufts, also has a background in engineering. He became a mentor to Myers and continues to collaborate with her today. He says Myers' and Vink's research on the cervix is particularly important.

HOUSE: A cervix problem is a tough one because a cervix problem can affect the pregnancy very early.

KODJAK: That means women with cervix problems are more likely to miscarry or give birth so early that their babies may die or face lifelong health problems. House says nailing down the mechanics of pregnancy is crucial to reducing premature birth. So Myers is laying the foundation - how much the uterus can stretch, how much pressure is on the cervix, what makes it open, how much force a baby's kick puts on the whole system. She has a lab next to Vink's at the medical center and another at Columbia's engineering school.

MYERS: So here's my lab.

KODJAK: There are four students sitting elbow to elbow at computers.

MYERS: So here in New York City, we run a tight, efficient ship. This is a 600-square-feet biomechanics lab.

KODJAK: On one screen, there's a multicolored three-dimensional image of the cervix that changes as the researchers add variables like a baby's kick. On the other side of a partition, there are microscopes and scalpels and slides.

MYERS: On this bench over here is a contraption we made to mechanically test thin membranes.

KODJAK: The machine inflates uterine membranes like a balloon. And there's another machine about the size of a microwave that stretches cervical tissue between two tiny grips.

MYERS: In civil engineering, you can have one of these machines that is, like, two, three stories high. And they're testing the mechanical strength of, like, railroad ties.

KODJAK: One of the most remarkable things about the cervix, Myers says, is how much it changes during pregnancy. Remember nose to butter?

MYERS: Pregnant tissue is really, really soft and squishy. So we've mechanically tested various pregnant tissues and non-pregnant tissues of the cervix, and its stiffness changes by three orders of magnitude.

KODJAK: Myers is also building an entirely new database of the anatomy of pregnant women using ultrasound images that measure the baby and the mother throughout pregnancy. She says she got the idea when she was pregnant and getting an ultrasound herself.

MYERS: Laying there on the bench, I was like, well, why can't we just measure the mom more?

KODJAK: The plan is to use that data to create a model that can predict how the uterus and cervix will react to various forces.

MYERS: What if the baby's kicking rigorously? How much mechanical force does it put on? What if the woman's at bed rest? How much does that take gravity off of her cervix? And, you know, we just don't know.

KODJAK: Vink and Myers are in constant contact. Myers' students observe Vink in the operating room as she collects tissue samples, and Vink reviews Myers' computer simulations. Their goal? To be able to look at a pregnant woman and predict accurately if she will go into labor prematurely. Only then can doctors find reliable interventions to stop it, which is what Brittney Crystal is aiming for as well. After Iris died, Crystal started a foundation called The Iris Fund, which has raised more than $150,000 for Vink's and Myers' research.

CRYSTAL: She didn't get to have a life, but we really want her to have a very strong legacy.

KODJAK: Alison Kodjak, NPR News, New York.

(SOUNDBITE OF DO MAKE SAY THINK'S "HERSTORY OF GLORY")