Baby born from egg matured in the lab and frozen
French fertility doctors have announced what is claimed to be the first baby to be born from an immature egg that was matured in the laboratory, frozen, then thawed and fertilised years later — a breakthrough that has now been documented in the journal Annals of Oncology.
Professor Michaël Grynberg, Head of the Department of Reproductive Medicine and Fertility Preservation at the Antoine Béclère University Hospital, described how he provided fertility counselling to a 29-year-old patient following her diagnosis with breast cancer. Ultrasound revealed there were 17 small fluid-filled sacs containing immature eggs in the woman’s ovaries, but using hormones to stimulate her ovaries to ripen the eggs would have taken too long and could have made her cancer worse.
An emergency procedure was scheduled six days later without ovarian stimulation, and Prof Grynberg retrieved seven immature eggs before the woman’s chemotherapy started. A process called in vitro maturation (IVM) was used to enable the eggs to develop further in the laboratory; the mature eggs were then frozen by means of vitrification, which freezes them very rapidly in liquid nitrogen to reduce the chances of ice crystals forming and damaging the cell.
“IVM enables us to freeze eggs or embryos in urgent situations or when it would be hazardous for the patient to undergo ovarian stimulation,” Prof Grynberg noted. “In addition, using them is not associated with a risk of cancer recurrence.
After five years, the patient had recovered from breast cancer but found that she was unable to conceive. Stimulating her ovaries to prompt them to produce more eggs ran the risk that the hormones used could cause the breast cancer to recur, so she and her doctors decided to use her frozen eggs. All six eggs survived the thawing process and they were fertilised using ICSI (intracytoplasmic sperm injection); five fertilised successfully and one embryo was transferred to the patient’s womb. She became pregnant and nine months later gave birth to a healthy baby boy named Jules.
“We were delighted that the patient became pregnant without any difficulty and successfully delivered a healthy baby at term,” Prof Grynberg said. “My team and I trusted that IVM could work when ovarian stimulation was not feasible. Therefore, we have accumulated lots of eggs that have been vitrified following IVM for cancer patients and we expected to be the first team to achieve a live birth this way. We continue offering IVM to our patients in combination with ovarian tissue cryopreservation when ovarian stimulation cannot be considered.”
Until now, there have been no successful pregnancies in cancer patients after eggs that have undergone IVM and vitrification, although some children have been born as a result of IVM followed by immediate fertilisation and transfer to the patient without freezing.
“Fertility preservation should always be considered as part of the treatment for young cancer patients,” Prof Grynberg added. “Egg or embryo vitrification after ovarian stimulation is still the most established and efficient option. However, for some patients, ovarian stimulation isn’t feasible due to the need for urgent cancer treatment or some other contraindication. In these situations, freezing ovarian tissue is an option but requires a laparoscopic procedure and, in addition, in some diseases it runs the risk of reintroducing malignant cells when the tissue is transplanted back into the patient.
“We are aware that eggs matured in the lab are of lower quality when compared to those obtained after ovarian stimulation. However, our success with Jules shows that this technique should be considered a viable option for female fertility preservation, ideally combined with ovarian tissue cryopreservation as well.”
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