For most parents, their child's fertility doesn't really cross their mind until their son or daughter reaches child-bearing years. But given that cancer treatments can slash fertility outcomes, some parents are having to consider the issue before they even reach puberty.
Melbourne mum Amy* was still changing her toddler Eleanor*'s nappy when she had to take measures to preserve Eleanor's chances of having a family for herself.
Amy had taken her 15-month-old girl to hospital with cold and flu symptoms in 2013 but within a couple of days was shocked to be informed her little girl had a brain tumour.
"They gave us a lot of information to read … and the chemo drugs' side effects were fertility," Amy recalls.
Amid the stress of the diagnosis, Amy spoke to the Melbourne Royal Children's Hospital Gynaecology Department about fertility preservation treatment.
"I'm hopeful that in the next 20-odd years there is going to be some research that will enable embryos to be grown from tissue that was taken out a while ago."
She decided to have part of Eleanor's ovarian tissue removed via keyhole surgery while Eleanor was having another surgery done, prior to starting chemo.
"It's comforting to know that she has some tissue preserved," Amy says. "She's not going to need it for 25 to 30 years and I'm hopeful that in the next 20-odd years there is going to be some research that will enable embryos to be grown from tissue that was taken out a while ago."
Fertility preservation for childhood cancer patients is still very much in its infancy but it's recently become part of the discussion at Royal Children's Hospital, where over 100 procedures have been undertaken.
Associate Professor Kate Stern, head of the Fertility Preservation Service at Melbourne IVF and the Women's Hospital, says parents are often buoyed by the fact doctors are not just talking about helping their child survive, but are considering their life decades down the track. "They completely appreciate a discussion about it," she says.
For girls, it involves taking "slices" of ovarian tissue to freeze and graft back into the pelvis at a later date if she does not go through puberty or encounters fertility issues.
"We try not to give the impression that it means that everything's going to be OK."
This treatment has proved quite successful when used with adult patients but time will tell if it proves successful for children.
"There have been over 60 births in women who have had tissue taken post-childhood so we know that we can do it," Ass Prof Stern says. "But there's only been one birth in tissue put back from someone who was a little girl."
For now, parents who choose this action for their daughters down are informed there is no guarantee of grandchildren.
"We're offering it to all families where there's curative intent and the medical risk is low," explains Dr Yasmin Jayasinghe, paediatric gynaecologist and lead investigator of the Fertility Preservation Taskforce at the Royal Children's Hospital. "[But] we try not to give the impression that it means that everything's going to be OK."
For boys who don't yet produce sperm, the Royal Children's Hospital in Melbourne offers testicular tissue biopsy.
"A tiny piece of tissue is collected under anaesthetic and stored," says Dr Jayasinghe, who is supported by the Victorian Cancer Agency.
Scientists have not yet been able to make sperm from this tissue, so for now it's a matter of storing it in the hope of medical advances by the time the boys want to start their own families.
"Getting the immature sperm into mature sperm is a complex, difficult process but the fertility world is confident that we'll be able to get mature sperm by later grafting," Dr Stern explains.
"Some treatments' risk of infertility can be 90 to 100 per cent."
Not all childhood cancer treatments affect fertility, and new research shows female survivors of childhood cancer generally have a 70 per cent chance of still being able to conceive a family.
Dr Stern says bone marrow transplants and radiation done in the pelvic region are particularly risky for fertility, and the strength of the dose of chemotherapy and radiotherapy can also alter risk. "Some treatments' risk of infertility can be 90 to 100 per cent," Dr Jayasinghe says.
Until recently, most childhood cancer treatment was focused on keeping the child alive, but fertility discussions have become par for the course with the increase in survival rates, says Dr Jayasinghe.
"Numerous studies show that a lack of information about fertility and reproductive health at the time of diagnosis and throughout treatment and survivorship increases anxiety and distress," she explains.
"International guidelines recommend that the impact of cancer treatment on fertility is discussed with all patients where there's curative intent."
Not for all
Many patients won't need fertility preservation and for some it will be deemed too risky. "We try and predict the impact [of treatment on fertility] based on all of the past literature, but that's not an exact science," explains Dr Jayasinghe. "[For example] if we collect ovarian tissue that might have cancer cells in it, then re-implanting that at a later date might be an issue."
Melbourne mum Tania has been left with lingering concerns about her daughter Rosie*'s future fertility after she had chemotherapy for rhabdomyosarcoma, a highly malignant cancer, three years ago when she was two.
"I was aware that chemo and cancer treatment does affect fertility but [fertility preservation treatment] didn't come up," she says. "She loves children and it's hard when you see kids that love kids and think, 'Maybe you are not going to have that'."
Tania is pleased to hear that parents of kids with cancer are now talked through fertility options, and she is hopeful that there will be treatments available for Rosie if she ever encounters fertility problems.
"There is a chance that once she hits puberty we can try and freeze some eggs in case her ovaries fail early, as they can for females who have gone through chemo," Tania says.
Amy understands there are no promises that Eleanor's fertility has been preserved, but she's glad that they've given her daughter the best possible chance of having a family for herself.
"We were warned that it's still guinea pig stage and there's no guarantee anything will come out of it," she says. "But to know that we've got something there to be able to use is comforting."
*Names have been changed
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