Never too old? |
MENOPAUSE
need not be the end of fertility. A team claims to have found a way to
rejuvenate post-menopausal ovaries, enabling them to release fertile eggs, New
Scientist can reveal.
The team says
its technique has restarted periods in menopausal women, including one who had
not menstruated in five years. If the results hold up to wider scrutiny, the
technique may boost declining fertility in older women, allow women with early
menopause to get pregnant, and help stave off the detrimental health effects of
menopause.
“It offers a
window of hope that menopausal women will be able to get pregnant using their
own genetic material,” says Konstantinos Sfakianoudis, a gynaecologist at the
Greek fertility clinic Genesis Athens.
“It is
potentially quite exciting,” says Roger Sturmey at Hull York Medical School in
the UK. “But it also opens up ethical questions over what the upper age limit
of mothers should be.”
Women are
thought to be born with all their eggs. Between puberty and the menopause, this
number steadily dwindles, with fertility thought to peak in the early 20s.
Around the age of 50, which is when menopause normally occurs, the ovaries stop
releasing eggs – but most women are already largely infertile by this point, as
ovulation becomes more infrequent in the run-up. The menopause comes
all-too-soon for many women, says Sfakianoudis.
The age of
motherhood is creeping up, and more women are having children in their 40s than
ever before. But as more women delay pregnancy, many find themselves struggling
to get pregnant. Women who hope to conceive later in life are increasingly
turning to IVF and egg freezing, but neither are a reliable back-up option .
The menopause
also comes early – before the age of 40 – for around 1 per cent of women,
either because of a medical condition or certain cancer treatments, for
example.
“It offers
hope that menopausal women will be able to get pregnant using their own genetic
material“
To turn back
the fertility clock for women who have experienced early menopause,
Sfakianoudis and his colleagues have turned to a blood treatment that is used
to help wounds heal faster.
Platelet-rich
plasma (PRP) is made by centrifuging a sample of a person’s blood to isolate
growth factors – molecules that trigger the growth of tissue and blood vessels.
It is widely used to speed the repair of damaged bones and muscles, although
its effectiveness is unclear.. The treatment may work by stimulating tissue
regeneration.
Sfakianoudis’s
team has found that PRP also seems to rejuvenate older ovaries, and presented
some of their results at the European Society of Human Reproduction and Embryology annual meeting in
Helsinki, Finland, this month. When they injected PRP into the ovaries of
menopausal women, they say it restarted their menstrual cycles, and enabled
them to collect and fertilise the eggs that were released.
“I had a
patient whose menopause had established five years ago, at the age of 40,” says
Sfakianoudis. Six months after the team injected PRP into her ovaries, she
experienced her first period since menopause.
Sfakianoudis’s
team has since been able to collect three eggs from this woman. The researchers
say they have successfully fertilised two using her husband’s sperm. These
embryos are now on ice – the team is waiting until there are at least three
before implanting some in her uterus.
The team
isn’t sure how this technique works, but it may be that the PRP stimulates stem
cells. Some research suggests a small number of stem cells continue making new
eggs throughout a woman’s life, but we don’t know much about these yet. It’s
possible that growth factors encourage such stem cells to regenerate tissue and
produce ovulation hormones. “It’s biologically plausible,” says Sturmey.
Fertilised eggs
Sfakianoudis’s
team says it has given PRP in this way to around 30 women between the ages of
46 and 49, all of whom want to have children. The researchers say they have
managed to isolate and fertilise eggs from most of them.
“It seems to
work in about two-thirds of cases,” says Sfakianoudis. “We see changes in
biochemical patterns, a restoration of menses, and egg recruitment and
fertilisation.” His team has yet to implant any embryos in post-menopausal
women, but hopes to do so in the coming months.
PRP has
already been helpful for pregnancy in another group of women, says
Sfakianoudis. Around 10 per cent of women who seek fertility treatment at his
clinic have a uterus that embryos find difficult to attach to – whether due to
cysts, scarring from miscarriages or having a thin uterine lining. “They are
the most difficult to treat,” says Sfakianoudis.
But after
injecting PRP into the uteruses of six women who had had multiple miscarriages
and failed IVF attempts, three became pregnant through IVF. “They are now in
their second trimester,” says Sfakianoudis.
Fertility
aside, the technique could also be desirable for women who aren’t trying to
conceive. The hormonal changes that trigger menopause can also make the heart,
skin and bones more vulnerable to ageing and disease, while hot flushes can be
very unpleasant. Many women are reluctant to take hormone replacement therapy
to reduce these because of its link with breast cancer. Rejuvenating the
ovaries with PRP could provide an alternative way to boost the supply of
youthful hormones, delaying menopause symptoms.
However,
Sfakianoudis’s team hasn’t yet published any of its findings. “We need larger
studies before we can know for sure how effective the treatment is,” says
Sfakianoudis.
Some have
raised concerns about the safety and efficacy of the procedure, saying the team
should have tested the approach in animals first. “This experiment would not
have been allowed to take place in the UK,” says Sturmey. “The researchers need
to do some more work to make sure that the resulting eggs are OK,” saysAdam
Balen at the British Fertility Society.
To know if
the technique really does improve fertility, the team will also need to carry
out randomised trials, in which a control group isn’t given PRP.
Virginia Bolton, an embryologist at Guy’s
and St Thomas’ Hospital in London, is also sceptical. “It is dangerous to get
excited about something before you have sufficient evidence it works,” she
says. New techniques often find their way into the fertility clinic without
strong evidence, thanks to huge demand from people who are often willing to
spend their life savings to have a child, she says.
If the
technique does hold up under further investigation, it could raise ethical
questions over the upper age limits of pregnancy – and whether there should be
any. “I lay awake last night turning this over in my mind,” says Sturmey.
“Where would the line be drawn?”
Health issues
like gestational diabetes, pre-eclampsia and miscarriage are all more common in
older women. “It would require a big debate,” says Sturmey.
SOURCE: NEW SCIENTIST
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