Canadian scientists have announced the birth of the first baby to be produced from an egg, that was developed in a test tube, and then frozen and defrosted for later use.
The news provides hope for women who have had sudden ovarian failure or who cannot be administered drugs that help egg maturation in the ovaries themselves.
AdvertisementThe baby girl, who is now around one year old, was born in Canada after work at the McGill Reproductive Centre in Montreal. The baby's mother has a medical condition called polycystic ovarian syndrome, where ovaries can get over-stimulated if she is given hormone injections that are routinely used by fertility doctors to obtain mature eggs.
Researchers led by Hananel Holzer isolated unmatured egg cells from the woman's ovaries and used hormones to wheedle them to maturity in the laboratory. They froze the eggs and thawed for use.
Though the maturation of eggs in the lab has been done before, leading to healthy births, and the freezing of eggs is a well-established procedure, this is the first time that all these procedures have been linked into a successful birth.
Three more women from the 20 participants in the study are also now pregnant, giving a 20pct overall success rate. The success shows that eggs that have been matured in the test tube and then frozen can still generate a full-term pregnancy
"We have demonstrated for the first time that it is possible to do this," Nature quoted Holzer, as saying.
The technique can also benefit women with cancers, such as breast cancer, and those undergoing in vitro fertilization (IVF), where they are typically given female hormone supplements to boost the number of mature eggs they produce, allowing more embryos to be created.
"Ovarian stimulation is also time-consuming, taking between two and six weeks. Women who suffer sudden ovarian failure would not have time to wait for traditional methods, and so the new technique could therefore help them save and freeze several eggs before it is too late," Holzer said.
"The technique has not yet successfully been demonstrated in cancer patients, who might be expected to make up the majority of those wishing to preserve their fertility using this method," Holzer added.
Holzer suggested that healthy women can actually resort to this procedure to preserve their fertility as they near middle age.
"Women in their mid-30s with no partner could freeze their eggs in this way," he told the meeting," he said.