<tt id="6hsgl"><pre id="6hsgl"><pre id="6hsgl"></pre></pre></tt>
          <nav id="6hsgl"><th id="6hsgl"></th></nav>
          国产免费网站看v片元遮挡,一亚洲一区二区中文字幕,波多野结衣一区二区免费视频,天天色综网,久久综合给合久久狠狠狠,男人的天堂av一二三区,午夜福利看片在线观看,亚洲中文字幕在线无码一区二区
          WORLD> Global General
          New ovarian transplant tech gives more hope
          (China Daily)
          Updated: 2009-06-30 08:58

          LONDON: Two new techniques to preserve and transplant ovaries might give women a better chance to fight their biological clocks and have children when they are older, doctors announced Monday.

          Related readings:
           Ovarian changes may link obesity and infertility
           Obesity may raise risk of ovarian cancer
           Study links ovarian cancer survival to gene change
           Experts list warning signs of ovarian cancer

          In the past, scientists have performed ovarian transplants in women with cancer, since chemotherapy often causes infertility. Doctors typically take out patients' ovaries before the toxic treatment begins and then reimplant them later.

          Because of the cost and uncertainties involved - only a handful have been done successfully - this was thought only worthwhile for women with serious diseases who had few options.

          Now, new advances to preserve ovaries and surgically implant them could make the procedure more widely available, helping women avoid fertility problems as they age. Many women are now delaying having a family until their 30s or 40s, when fertility problems are more common.

          Women in their 20s or 30s could theoretically have an ovary removed and frozen, and then have it reimplanted years later when they are ready to have children.

          "We are in the middle of an infertility epidemic," said Dr Sherman Silber, director of the St. Louis Infertility Center in Missouri. "With these new techniques, we could dramatically expand our reproductive lifespan."

          The research was reported at a meeting of the European Society of Human Reproduction and Embryology in Amsterdam.

          Silber and colleagues studied how many eggs were lost or preserved in fresh and frozen ovarian tissue of 15 young women before they had cancer treatment. The doctors found no difference in the number of eggs in fresh tissue and in ovaries frozen using a new ultra-fast technique.

          Using the traditional, slow-freezing methods of preserving ovaries, about half of a woman's eggs were lost.

          In related research, Dr Pascal Piver of Limoges University Hospital in France reported on a new surgical technique to transplant ovaries.

          Doctors have often found it difficult to restore an ovary's function after transplantation, largely because it takes time for the blood and hormone supply to be re-established.

          Piver and colleagues attempted to solve this problem by dividing the transplant into two procedures: an initial graft of small pieces of ovarian tissue to encourage blood vessels to grow put in place three days before the real transplant.

          The technique was used in a French woman who had been unable to have children because of treatment for sickle cell anemia. In June, she gave birth to a baby girl.

          "All of this research is a step in the right direction," said Pasquale Patrizio, of Yale University, who performs ovary transplants but was not connected to either study. "If we really have these techniques under control, maybe we can spread this technology to many more women."

          But Patrizio said doctors need to know how an ovary taken from a woman years ago will perform once it is put back in.

          "If I take an ovary from a woman who's 30 and then reimplant it 15 years later, will it function as if it's a 30-year-old's ovarian tissue, or will it reset to become 45?" he asked.

          Experts said the possibility of healthy women being offered ovary transplants would likely spark controversy.

          "This is not an experimental procedure for cancer patients anymore," Silber said. "The question is whether more women should be able to have this option."

          AP

          主站蜘蛛池模板: 999在线视频精品免费播放观看| 毛片无码一区二区三区| 九九热热久久这里只有精品| 97精品人妻系列无码人妻| 妺妺窝人体色WWW看人体| 国产精品亚洲日韩AⅤ在线观看| 青青操国产| 亚洲人成网站在线观看播放不卡| 亚洲国产色播AV在线| 爱啪啪av导航| 国产内射性高湖| 五月天天天综合精品无码| 国产精品中文字幕久久| 国产色无码专区在线观看| av深夜免费在线观看| 国产精品麻豆中文字幕| 高清无码爆乳潮喷在线观看| 国产精品久久中文字幕| 成人免费乱码大片a毛片| 麻豆国产成人AV在线播放| 综合偷自拍亚洲乱中文字幕| 亚洲日韩精品无码一区二区三区| 性欧美VIDEOFREE高清大喷水| 人妻少妇偷人精品一区| 日韩精品无码区免费专区| 最新亚洲av日韩av二区| 疯狂做受xxxx高潮欧美日本| 中文字幕在线无码一区二区三区| 亚洲av色精品一区二区| 国产精品亚洲综合网一区| jizz视频在线观看| 亚洲精品爆乳一区二区H| 国产一区二区三区怡红院| 国产毛多水多高潮高清| 又黄又爽又猛1000部a片| 国内精品久久久久影院薰衣草| 性色av不卡一区二区三区| 开心一区二区三区激情| 成码无人AV片在线电影网站| 亚洲国产精品一区二区第一页| 无卡国产精品|