A 28-year-old woman gave birth to a baby using ovarian tissue that was removed and frozen in her childhood and has become the first person in the world to have delivered a baby in such a way.

Earlier also, successful transplants resulting in pregnancies have made use of frozen ovary tissue removed from adult women. However, this case is different; it started when a girl was just 13 years and 11 months old.

It was unknown if tissue taken from girls prior to puberty could develop to produce eggs. The whole thing has been described in the journal Human Reproduction. Those young cancer victims, who undergo treatments such as chemotherapy that can damage the ovaries, making them infertile, could be benefited by this breakthrough.

The woman was born in the Republic of Congo. She moved to Belgium when she was 11 and received a transplant of her brother's bone marrow for treatment of her sickle-cell anaemia that required chemotherapy so as to disable the immune system and prevent rejection of the bone marrow.

Her right ovary was removed by doctors just before she turned 14 and after that they froze tissue fragments. Breast development and puberty had started; however, her periods had not began. After treatment, she was left with no functioning ovary and when she turned 15, doctors started hormone replacement therapy (HRT) in order to induce menstruation.

After 10 years, she wanted to start a family and doctors stopped the HRT and implanted four fragments of the frozen ovarian tissue on to the remaining left ovary and other fragments in the nearby area.