Despite setbacks, mom continues treatment, gets pregnant

BY BETH WHITEHOUSE | beth.whitehouse@newsday.com

At 6:15 a.m. on June 21, 2004, embryologist Wayne Caswell is riding west on the Long Island Expressway on his Kawasaki motorcycle. At the office of Reproductive Specialists of New York in Mineola, nine embryos are waiting for him in a petri dish the size of the top of a soda can. These embryos were created from eggs removed from Stacy Trebing's ovaries and fertilized with husband Steve's sperm.

At the laboratory, Caswell trades his leather jacket for blue scrubs. The hands that this morning tossed laundry into the dryer at home will now operate on embryos so small they can't be seen by the human eye.

Appropriately, Caswell's lab is stenciled with a playful ceiling border of sperm chasing an egg. The nine Trebing embryos are in an incubator that resembles a hotel room mini refrigerator. Caswell uses a tool that works like a miniature turkey baster to pick up embryo No. 1.

He transfers it to an individual dish and places it under a microscope. Through the lens, the eight-cell embryo looks like a soccer ball. It has a membrane, as if wrapped in plastic wrap. Caswell shoots a low intensity laser to burn a hole in the lining. Only then can he steal what he's after.

One cell.

Scientists know an embryo can survive the loss of one cell. During routine in vitro fertilization, embryos are often frozen for future use. One or two cells may die in the thawing process, but a fully formed human being can still grow. Nature also causes some embryos to divide in two, forming identical twins.

Caswell can't talk while working -- because he literally uses his breath to blow and suck the cell off the embryo. He now uses two pipettes -- one to steady the embryo and the other to manipulate it. With his left hand holding the pipette to the embryo, the second pipette goes in his mouth like a straw.

Extracting cell from embryos

In a laboratory filled with sophisticated equipment, Caswell uses a low-tech process that's much like sipping a cocktail through a straw. He blows or sucks, easing the cell off the embryo. As he does, the cell stretches like a water balloon -- first round, then oval, until it breaks free from the others and returns to a circle.

When he gets to embryo No. 4, Caswell notes its beauty: evenly sized, good symmetry. On the other hand, embryo No. 8 is severely abnormal -- it has advanced to only two cells. Such embryos would be unlikely to survive on their own.

"I can't biopsy this embryo," Caswell says. "We didn't cause that. It's just inherent in the egg. Many patients think you've retrieved this amount of eggs, I should have this number of babies available. We're doing things to screen. We're doing things to select. But we're not doing things to fix."

Of the nine embryos, Caswell is able to remove a single cell off of seven for testing.

"Seven's not a bad number," he says.

Finding a match for Katie

The cells are deep frozen in tubes and put into a cooler to be loaded onto a routine flight at Kennedy Airport and flown to geneticist Mark Hughes at the Genesis Genetics Institute in Detroit. Hughes has been preparing for the cells' arrival for weeks, examining Steve's, Stacy's and Katie's DNA to make sure he can match the embryos correctly. Once the cells get to him, Hughes and his team will spend the next 19 hours performing preimplantation genetic diagnosis (PGD) to determine which of the seven cells are an exact human leukocyte antigen match for Katie. Those antigens are a code in the DNA that tells the body's immune system that other cells belong and are not foreign invaders. Having matching antigens would allow Katie's body to accept a sibling's bone marrow.

Two days after the embryos arrive in Detroit, Stacy is anxious, but excited. At noon, she is scheduled to have embryos that match Katie implanted into her uterus. Stacy had a dream last night that, of the seven embryos tested, one was viable. It was implanted and she got pregnant with a girl.

Steve won't be going with Stacy for the implantation. It's the height of the season for his party tent business and he's already scheduled to take a week off in July to go with the family to Camp Sunshine on the coast of Maine. The camp is for families with children who have life-threatening diseases, devoting a week, for instance, to leukemia and another to Diamond Blackfan anemia.

With the emotional boost of her dream, Stacy feels the day holds promise. On Father's Day the previous weekend, Steve's Aunt Kathy gave Stacy a candle with an angel on it. Hoping for the best, she and Steve lit it last night. As Stacy heads to Mineola, she knows only seven embryos were tested and the odds are one in four will be an exact match for Katie. That's disappointing to the Trebings, because 19 eggs had been harvested and 14 had fertilized into embryos immediately. The Trebings were surprised to learn that in the end they only had seven from which to choose. Dr. James Stelling, who heads the PGD division of Reproductive Specialists of New York, explained to them that this kind of attrition is normal and it's one reason doctors stimulate women's ovaries to mature multiple eggs in a cycle.

When Stacy arrives, she learns that the results aren't complete yet. They will wait another day.

In medical school at Stony Brook University, Stelling was one of the few people in his class who knew he wanted to become a fertility doctor.