がん治療で不妊の女性、冷凍保存の体外成熟卵子で出産　世界初

【パリＡＦＰ＝時事】乳がん治療のための化学療法の影響で不妊になった女性（３４）が、事前に採取していた自身の未成熟卵子を使って５年後に出産した。未成熟卵子は採取後、体外で成熟され、冷凍されていた。フランスの研究チームが１９日、英医学誌「腫瘍学年報」で発表した。がん患者が卵子の体外成熟と凍結を経て妊娠に成功した事例は世界初だという。（写真は資料写真）
　医師らは化学療法を開始する前に、女性の卵巣から未成熟卵子７個を採取。未成熟卵子を体外で成熟させる「ＩＶＭ」と呼ばれる技術を使い、これらを実験室内で成熟させた。
　ホルモン剤によって卵巣を刺激する方法は時間がかかり過ぎるため、がんを悪化させる恐れがあった。このため、未成熟卵の採取と凍結が最善の方法として選択されたという。
　女性は５年後、乳がんから回復したが、化学療法の影響で自然妊娠ができなくなっていた。
　だが、5年前に凍結した卵子7個のうち6個の解凍に成功し、うち5個が受精できた。受精卵の一つを子宮に戻し、女性は2019年7月6日に健康な男児を出産した。男の子はジュールと名付けられた。【翻訳編集ＡＦＰＢＢＮｅｗｓ】
〔ＡＦＰ＝時事〕（2020/02/26-12:44）

In a world first, a woman rendered infertile by cancer treatment gave birth after one of her immature eggs was matured, frozen, and then -- five years later -- thawed and fertilised, researchers in France reported.
A study in the journal Annals of Oncology published Wednesday describes how the baby boy was born to a 34-year-old French woman who had been treated with chemotherapy for breast cancer.
Before the treatment began, doctors removed seven immature eggs from her ovaries and used a technique called in vitro maturation (IVM) to allow the eggs to develop further in the laboratory.
Up to now, there have been no successful pregnancies in cancer patients with eggs that have undergone IVM and freezing.
Some children, however, have been born as a result of IVM immediately followed by fertilisation and transfer to the patient.
Michael Grynberg, head of the Department of Reproductive Medicine and Fertility Preservation at Antoine Beclere University Hospital near Paris, recalled becoming aware of the 29-year-old patient's case.
I offered her the option of egg freezing after IVM, and also freezing ovarian tissue, he said in a statement.
She rejected the second option, which was considered too invasive a couple of days after cancer diagnosis.
So-called cryopreservation of ovarian tissue is an experimental method in which the outer layer of an ovary -- which contains immature eggs -- is taken out of the body and frozen for future use.
In the case of the French patient, ultrasound revealed that there were 17 small, fluid-filled sacs containing immature eggs in her ovaries.
But using hormones to stimulate the ovaries to ripen the eggs would have taken too long and might have made her cancer worse, leaving retrieval of the immature eggs and freezing as the best option.
After five years, the patient recovered from breast cancer, but she was unable to conceive naturally. The chemo had made her infertile.
Six of the eggs that had been frozen five years earlier survived the thawing process, and five were successfully fertilised.
One of these fertilised eggs was transferred to the patient's womb, and she gave birth to a healthy baby boy -- named Jules -- on July 6, 2019.
This success represents a breakthrough in the field of fertility preservation, Grynberg said.