In an experiment to see whether transplanted wombs could allow women without a uterus to give birth, nine women in Sweden who have received wombs from live donors are hoping to be the first to bear children.

“This is a new kind of surgery,” Dr. Mats Brannstrom told The Associated Press. “We have no textbook to look at.”

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Two previous transplants never resulted in babies. So far, the transplanted wombs seem to be functioning: Some of the women had their periods, a likely signal of a healthy uterus. The first embryos, which were created from the women’s own eggs and frozen before the operation, could be transferred to the wombs within months.

The transplants are intended to be temporary. Because the women must take anti-rejection drugs that can cause side effects such as high blood pressure and diabetes, the wombs will be removed after one or two pregnancies.

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Such a novel use of transplants has caused some ethical questions, however. In Britain, for example, the risk to the donor is considered too great for a non life-threatening procedure.

“Mats has done something amazing and we understand completely why he has taken this route, but we are wary of that approach,” Dr. Richard Smith, head of the U.K. charity Womb Transplant UK, told AP.

Smith’s organization is trying to raise money to help doctors in Britain can perform similar transplants using wombs from dying or deceased donors.

Photo: University of Gothenburg/YouTube Screen Capture