He said doctors have to balance patient autonomy with ethical choices. "Beneficence is an important part of it ... doing good for the children," he said. "That's where [Kamrava] failed."
Having twins, not to mention just eight children, carries risks for both mother and her babies.
"For the mother, it's less severe; diabetes and hypertension," Stillman said. "There can be months and months of bed rest with clots and embolisms.
"For the infant, the risks are lifelong: prematurity, cerebral palsy, blindness, months in intensive care. You can go through a litany of things for people who want to have a family. I have this discussion every day."
Indeed, one of Stillman's patients this week lost twins at 20 weeks gestation. "This is the side of twins people don't see," he said.
And it's not just heterosexual couples who are pressuring doctors.
"About 95 to 99 percent of gay couples want twins," said Karen Synesiou, director of the Center for Surrogate Parenting, which has facilities in California and Maryland.
A surrogate mother's eggs are divided in half and fertilized with each of the men's sperm. One from each potential father is then transferred.
"The success rate is so high with egg donors who have had previous pregnancies," she said. "You put a donor in the mix and you only need to get one pregnancy."
Of the 100 couples the center serves each year, 48 percent are gay.
Synesiou said the trend jeopardizes the surrogate industry as a woman can only safely carry one set of twins to term.
"She delivers earlier," Synesiou said. "There are higher medical costs for twins, who are already four weeks early and born under 5 pounds. My job is to help couples be parents and we want them one at a time, the chunky 8-pound babies."
In an effort to reduce multiple births, the American Society for Reproductive Medicine revised its guidelines in 2007, recommending transfer of one embryo for patients with a good prognosis (two for those with a poor prognosis) for each IVF cycle for women younger than 35.
That number can increase up to five for women with failed cycles or those older than 42.
The American Society for Reproductive Medicine says it has a "strong ethical process" and clear guidelines on embryo transfer, but not "where doctors should draw the line with their patients," spokesman Sean Tipton said.
"There can be tensions between patient autonomy and a physician's professional judgment, however a patient's does not have the right to demand the physician practice dangerous medicine," he said.
But Dr. Jamie A. Grifo, program director for the New York University Fertility Center, said there is "a lot of wiggle room in the guidelines."
"The chance of getting octuplets from six implants is one in a billion," he said. "Part of this case is that it's such a statistical fluke. No one measures what it costs to regulate something like this. There's no metrics for that. You're not going to regulate a one in a billion event."
"When given the data, most people make the right decision," Grifo said. "If you don't present it to your patient, you don't have a shot at making the best decisions.
"Every patient is different and that's why you have doctors, to understand the complexities," he said. "If you try to practice medicine by guidelines alone, you will harm more patients than you help."