An 11-month-old baby is living proof of a new fertility treatment that could give the chance of motherhood to thousands of young girls suffering from cancer. The technique could also help women suffering from polycystic ovarian syndrome (PCOS) to have children with less risk.

Carine, who is healthy and developing normally, is the first baby to be conceived from an egg that was frozen after being matured in the laboratory.

Three other women in Canada are pregnant after having similar therapy. The achievement shows that it is possible to preserve fertility by freezing eggs without recourse to powerful hormonal drugs that stimulate the ovaries. While hundreds of children have been born from immature eggs that were ripened in a test tube before they were fertilised, Carine is the first to come from an artificially matured egg that was frozen and thawed.

This makes the work highly significant for female cancer patients, particularly for prepubescent girls and women who have hormone-sensitive tumours, as these groups cannot take fertility drugs to induce their ovaries to produce mature eggs for storage on ice. Instead, they can have immature eggs collected and cultured in the laboratory before freezing, which can then be thawed later if they want a family.

On Sunday, an Israeli team reported that it was possible to extract immature eggs from the ovaries of girls as young as 5, and the birth now indicates that it should be possible for these to be fertilised to conceive healthy children. The success is also promising for other infertile women who cannot take fertility drugs, or who prefer to avoid them because of side-effects that can include menopausal symptoms.

Patients who are infertile because they have PCOS, which affects about one in twelve women of reproductive age, are often advised against these drugs, as they have a high risk of developing ovarian hyperstimulation as a result. While PCOS patients can already benefit from having eggs matured in the lab and used while fresh, they can now freeze any that are left over for future attempts at IVF. The first four pregnancies were achieved from a trial of 20 Canadian women with PCOS.

Hahanel Holzer, who led the McGill University team in Canada, told the European Society of Human Reproduction and Embryology Conference in Lyons that the pregnancies prove the technique gives a new range of options to women wishing to protect their fertility.

“It has the potential to become one of the main options for fertility preservation, especially for patients who cannot have ovarian stimulation and all patients who do not have enough time to undergo ovarian stimulation,” he said. “However, we have to remember that these are only preliminary results from a small number of patients who were not cancer patients themselves.”

Independent fertility specialists including Lord Winston, Emeritus Professor of Fertility Studies at Imperial College, London, welcomed the research, though they cautioned that more work is needed before freezing artificially matured eggs can be considered a standard treatment.

The new technique

— Polycystic ovarian syndrome is a condition in which cysts form in the ovaries, often causing infertility

— In standard IVF treatment, women take hormonal drugs to stimulate their ovaries before egg collection. This means they produce multiple mature eggs, instead of the one that is normally ovulated in every menstrual cycle

— PCOS patients are often advised against using fertility drugs, as they are at higher risk of suffering ovarian hyperstimulation syndrome as a result. This causes pain, nausea, and in rare cases cause kidney failure and death

— In the new treatment instead of taking fertility drugs, the women had several immature eggs removed from her ovaries. These were then ripened in the laboratory, using a procedure known as in-vitro maturation, and frozen for future use

— IVM was developed in the late 1990s, and has been used in about 1,000 births

— The birth of Carine is is the first occasion in which an IVM egg that has been frozen has produced a pregnancy. Twenty patients with PCOS took part in the trial that led to her birth

Source: McGill University, Times database

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