Doctors described Wednesday as a world first, when a Danish woman gave birth to two children after her fertility was restored using ovarian tissue that was removed, frozen, thawed and then reimplanted after cancer treatment.
It is being hailed as a breakthrough for young women whose hope of one day becoming mothers could be wrecked by cancer therapy in their reproductive years.
Stinne Holm Bergholdt, from Odense, Denmark, was diagnosed with a cancer type known as Ewing's sarcoma in 2004, when she was 27.
Before she began chemotherapy, part of her right ovary was removed and frozen. Her left ovary had already been removed some years earlier after doctors found a cyst that turned out to be benign.
The cancer treatment was a success but, as usually happens in such therapy, the drugs brought the onset of menopause.
In December 2005, six thin strips of ovarian tissue were transplanted back on to what remained of her right ovary, and began to function normally, according to the case reported by the European Society of Human Reproduction and Embryology (ESHRE) in its journal Human Reproduction.
After a brief course of hormones to stimulate egg production, Bergholdt became pregnant again and gave birth to her first daughter, Aviaja, in February 2007.
In 2008, she returned to her fertility clinic, seeking in-vitro fertility (IVF) treatment in the hope of conceiving again.
But a pregnancy test showed that she was already pregnant through natural means, and in September 2008, she gave birth to another girl, Lucca.
Seven other children have been born around the world using the so-called cryopreservation technique, but this is the first time it has helped a woman to have two babies.
"These results support cryopreservation of ovarian tissue as a valid method of fertility preservation and should encourage the development of this technique as a clinical procedure for girls and young women facing treatment that could damage their ovaries," said her physician, Claus Yding Andersen, a professor at the University Hospital of Copenhagen.
Bergholdt is even having to use "pregnancy-preventing measures" to avoid a pregnancy right now, said Andersen.
In a press release, Bergholdt described the experience as "a miracle."
"When I found out I was pregnant for the first time I was of course very happy and excited -- but also very afraid and sceptical since I found it very hard to believe that my body was really working again," she said.
"The second time it was quite a surprise to find out I was pregnant since we hadn't been working on it -- we thought we needed assistance like the first time... It was a very nice surprise to find out that my body was now functioning normally and that we were having a baby without having to go through the fertility treatment."
She and her husband have not decided yet whether they wanted more children, she added.
"The girls are still so small and need a lot of attention, but maybe in a couple of years we might think about it again."