They make sense of baby's first picture

Drs. Carol Benson and Peter Doubilet, of Brigham and Women's Hospital, enjoy unraveling the puzzle of ultrasound images. (Suzanne Kreiter/Globe Staff)

Their first reaction - these expectant parents - is to go wild. They look at the screen and see this grey image, this itty-bitty thing with the physique of Homer Simpson, and they freak out. This is real. They're pregnant. This is their baby, and they can see it with their own eyes.

Drs. Peter Doubilet and Carol Benson love this part.

Twenty minutes later, after a quick explanation from the doctors, the nervous parents go home, where they pull out a magnet and stick the ultrasound image on the fridge and stare at it. Constantly. Lost. For many parents, baby's first picture is a puzzle.

"I thought it looked like an alien," said Angela Brown, a 24-year-old nutrition educator from Quincy who is four months pregnant. "I couldn't tell what was going on, why one arm looked longer than the other. I definitely stared at it."

If a picture is worth a thousand words, then an ultrasound image of a fetus is a Rorschach test capable of inspiring a thousand pleasures, and a thousand panics. Parents ask: What am I looking at? What is this thing?

This is where Doubilet and Benson, a husband-and-wife duo who are both radiologists specializing in obstetric ultrasound at Brigham and Women's Hospital and full professors at Harvard Medical School, are trying to fill the void. They have five children between them. They know what these expectant parents are going through. So they decided to create a tour guide to help make these "Rorschach fuzzy things make sense," according to Benson.

The doctors like puzzles, and they say the riddles contained in radiology images satisfy that yen. Doubilet is a Life Master in bridge, and a former mathematician with a PhD from MIT who says he moved to medicine to connect with humans, and human puzzles. Benson became a radiologist specifically because it's not long-term treatment but short-term puzzle solving.

"It suits my personality," she said. "You're presented with a problem, analyze it, and move on to the next puzzle."

Expectant parents do not move on so quickly. That ultrasound image becomes the puzzle that's going to change their lives, and, until the little one is born, that's all they've got to go on.

So Doubilet, 59, and Benson, 53, created "Your Developing Baby: Conception to Birth," a new book that functions as a cipher to the image puzzle. With clear, simple text, and accompanying illustrations from Doubilet, the book aims to fill in everything a doctor can't in a 20-minute visit in the clinic.

As they pull up some images on a computer screen, it's clear that after 20 years of taking fetal portraits, Doubilet and Benson still get excited by what they're seeing.

"If I could have seen one of these pictures of my babies," Doubilet said, pointing to a 3-D ultrasound image, a relatively recent technology in which sound waves are sent into the fetus at multiple angles to create an external view of the baby, "I would have gone crazy."

"Look at this one," Benson chimed in, a big smile on her face, as she pulled up a series of video clips. "He's only 12 weeks and he's punching. . . . This one's mouth is moving. . . . This one is chewing on his fingers. . . . They're so fun."

While the primary goal of an ultrasound is diagnostic, bad news is, thankfully, rare, and that's why they say that of all the radiology specialties, working with expectant mothers is their favorite.

"When you have a mother who has had trouble conceiving in the past, and they have a positive pregnancy, they don't believe it until they see it," Benson said. "And that's an amazing moment."

"In radiology," Doubilet said. "You deal with all kinds of images. But usually, the patient comes in and the best you can tell them is 'You're fine.' The worst is 'You're not.' The range of emotion is from terrible to neutral. With babies, they can have a real thrill."

After 14 years of marriage - they met in the radiology department at Brigham and Women's - Benson and Doubilet recently experienced a parental milestone of their own: They just sent their last two children off to college. So they sold their house in Weston and moved to Copley Square to start a new experience together as empty-nesters.

"Now our commute is minutes," Benson said. "And our carbon footprint is a fraction of what it used to be. We walk everywhere. We hardly ever use the Prius."

They work together, they live together, they travel and lecture together, they wrote a book together, and they get sore together every summer on their annual 900-mile bike ride. How do they pull it off?

"We've learned to define who the primary person is for each thing," Benson said. "So when we butt heads, we know who will win."

Fact sheet

Hometowns: Benson is from Haddonfield, N.J.; Doubilet is from Montreal; they live in Copley Square.

Education: Benson earned her bachelor's degree in biology from Brown University in 1976, and her MD from the University of Pennsylvania in 1980; Doubilet has a bachelor's from McGill University, 1969, and a PhD from MIT, 1973, both in mathematics, and an MD from Columbia University in 1977.

Family: The couple have five children from previous marriages: Jennifer Doubilet, 30, teaches at the Driscoll School in Brookline; Steven Doubilet, 26, works for Google; Nicole Benson, 21, is a junior at Haverford College; Ben Benson, 19, is a freshman at Middlebury College; Sarah Doubilet, 19, is a freshman at the University of Chicago.

Hobbies: Benson was once the number one women's squash player in the state; Doubilet is a Life Master in bridge; they are avid cyclists who make a two-week, 900-mile trek each summer.