The survey, of more than 1,000 U.S. adults, asked people about their views on "posthumous reproduction."

Most often, that involves eggs, sperm or embryos that were frozen by a person before undergoing medical treatment that could cause infertility -- usually chemotherapy or radiation for cancer. If that person dies, their surviving partner may use the eggs or sperm to have a child through assisted reproduction.

In those cases, couples would have typically planned for, and documented, what should be done with the sperm or eggs if the ill partner died.

But in recent years, it's become possible to do "emergency" retrieval of sperm or eggs when someone suddenly dies or becomes terminally ill.

The typical situation involves a young couple who planned on having children-but never thought about what to do if one of them died unexpectedly, according to Dr. Sara E. Barton of Brigham and Women's Hospital in Boston.

"In those cases, there is virtually never any written directive," said Barton, who led the new study.

Emergency requests to harvest sperm or eggs are not common. At Brigham and Women's fertility center, doctors have gotten one or two such requests per year in the past few years, according to Barton.

But doctors don't have clear guidance on how to handle emergency requests. And an important factor is public opinion, Barton said.

So she and her colleagues tried to gauge people's attitudes in an online survey of 1,049 Americans ages 18 to 75.

After reading a short explanation of what "posthumous reproduction" is, close half of the respondents said they thought a person should be able to request sperm or eggs be taken from their dead or dying partner. About one-fifth said they "didn't know," while the rest were opposed.

But most people felt that should only be done if there was written consent from the deceased. Of people who supported posthumous reproduction, 70 percent said written consent should be mandatory.

Having mandatory written consent would, in reality, mean that most emergency requests could not be filled, Barton noted.

"I think our findings put into question doing the (emergency) retrieval at all," Barton said.

The study, which appears in the journal Fertility & Sterility, also asked people what they would want for themselves.

Half of respondents said they would not want sperm or eggs taken from them if they died-including 41 percent of respondents who were still in their reproductive years.

Barton pointed out that a couple can want to have children, but that does not necessarily mean someone would want to become a parent after he or she died.

EUROPEAN GUIDELINES

Right now, the American Society for Reproductive Medicine has no specific guidelines on emergency requests for sperm or egg retrieval. But the European Society for Human Reproduction and Embryology (ESHRE) does.

It says that written consent is a must, and there should be a minimum one-year waiting period before the frozen eggs or sperm are actually used.

"The general public seems to be in line with the ESHRE," Barton said -- though, on the issue of wait time, only about one-third of survey respondents thought there should be a mandatory one.

The study has its limits. It was an online survey, so it may not be representative of Americans as a whole.

And most respondents had never heard of "posthumous reproduction" before the survey. It's possible that with more information, people's attitudes could shift, according to Barton.

Now that people are starting to learn that emergency sperm and egg retrieval is possible, some couples may want to think about the issue. "This may be something you decide you want to talk about with your loved ones," Barton said.

SOURCE: bit.ly/NyUmz1 Fertility & Sterility, online July 3, 2012.

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