(Reuters) - Many people in the United States think it is okay to retrieve sperm or eggs from a dead or dying spouse in order to have children in the future, but only if there is written consent, according to a survey.

That poll of more than 1,000 U.S. adults appeared in the journal Fertility & Sterility and asked people about their views on posthumous reproduction.

Most often, the process involves egg, 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 somebody 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, said Sara Barton of Brigham and Women's Hospital in Boston, who led the study.

In those cases, there is virtually never any written directive, she said.

Emergency requests to harvest sperm or eggs are not common. At Brigham and Women's fertility center, doctors have had one or two such requests per year in the past few years, Barton said. But doctors do not have clear guidance on how to handle emergency requests.

Barton and her colleagues tried to gauge people's attitudes in an online survey of 1,049 people, aged 18 to 75.

After reading a short explanation of posthumous reproduction, close to half of the respondents said they thought a person should be able to request that sperm or eggs be taken from their dead or dying partner.

About one-fifth said they didn't know while the rest were opposed.

Most people felt it 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 - which would in reality mean that most emergency requests could not be filled, Barton said.

I think our findings put into question doing the (emergency) retrieval at all, she added.

The study also asked people what they would want for themselves.

Half of the 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.

At present, 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 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. SOURCE: bit.ly/NyUmz1

(Reporting from New York by Amy Norton at Reuters Health; editing by Elaine Lies and Bob Tourtellotte)

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