Assisted conception is the term applied to a range of fertility treatments that involve
handling eggs or sperm or both. In Britain, clinics that offer assisted conception are
all regulated through The Human Fertilisation and Embryology Authority. In the United States,
a different term is used: assisted reproductive technologies and their regulatory body is
called The Society for Assisted Reproductive Technologies. Over the years the commonest
treatment is IVF treatment. The very first success with IVF was in Britain in 1978 and
following on from that there's been a steady increase in the number of treatment cycles
being carried out. A key year in the advance of IVF was 1986. This is the introduction
of trans-vaginal scanning and also new drug treatments for ovarian stimulation for IVF
treatments. There was a further big step forward in 1992-93 with the introduction of intracytoplasmic
sperm injection. This is when sperm are injected directly into the eggs and this will apply
to couples who previously would have had failed fertilisation. Nowadays in Britain, about
1 in 50 babies born are born as the results of fertility treatment. So, it's no longer
the rare and unusual that it was at one time. Nowadays, many children aged 8, 9 and 10 will
know someone else at school who's been born as a result of fertility treatment.
The best-known assisted conception treatment is IVF, or to give it its full title in vitro
fertilisation, which involves stimulating the lady's ovaries, collecting eggs, fertilising
eggs in the laboratory and then subsequently transferring an embryo or sometimes two embryos
back to the uterus. If there's concern that the sperm might not be able to fertilise the
eggs, the sperm can be injected into the eggs one by one and this technique is called intracytoplasmic
sperm injection or ICSI. A much simpler treatment is intrauterine insemination treatment which
can be done in either natural or stimulated cycles and there's also the option with this
treatment to use donor sperm if it's a single lady or if the man does not have any sperm
of his own. Going back to IVF treatment, some women go through IVF but their ovaries don't
respond and then there are some women who have an early menopause and for those women
there's the option for treatment with donor eggs. So, she will have the donor eggs fertilised
with her partner's or husband's sperm and then embryos transferred back to her uterus.
If there are surplus embryos to requirements for the fresh cycle, so if after having transferred
one or two embryos there are good quality embryos remaining, these can be frozen and
then transferred in subsequent frozen embryo replacement cycles. An additional option with
IVF treatment is to biopsy the embryos. There are two techniques: pre-implantation genetic
screening and pre-implantation genetic diagnosis, and this ensures that only normal embryos
will be transferred back to the uterus. Some women will undergo IVF treatment but have
their eggs frozen rather than having the eggs fertilised. This might be a woman who's about
to start cancer treatment and wants to collect and store eggs before she starts on chemotherapy
or radiotherapy. And then there are also women who want to freeze eggs for future use in
case they might be infertile in future years.
Over the years there's been a steady increase
in the number of couples and single women who are wanting to access assisted conception
treatments. Of the various treatments available, IVF has proved to be the most popular and
this is for a variety of reasons not least of which is the fact that it's become more
successful over the years. There's a number of social changes that have also driven the
increased demand for fertility treatments and in particular many women nowadays choose
to delay having children into their 30s which unfortunately increases the chance that there
might be difficulties getting pregnant. The NHS has provided funding for some couples
wishing to pursue IVF treatment, but unfortunately there are often restrictive criteria which
mean there's a lot of couples who wish to access treatments are not able to secure NHS
funding. Another treatment that's proved popular is frozen embryo transfers. So, this is for
women or couples who've been through IVF treatments and there have been good-quality embryo surplus
to requirements, those of them been frozen and they can then be transferred in subsequent
frozen embryo replacement cycles. More recently, social egg freezing has become particularly
popular, and this is for women who are anxious to defer having children until later years,
but do not want to run the risk of being infertile. These women will go through all the stages
of IVF treatments up to and including egg collection, but then have the eggs frozen.
In future years, if they are unable to conceive naturally or with fertility treatments, there
will then be the option to go back and use the eggs which were frozen when they were
younger.
The success rates with IVF treatment is particularly
dependent on the woman's age. As the lady gets older, her eggs age with her and the
older eggs unfortunately do not perform as well in terms of fertilisation and developing
into good quality embryos. Another key reason that affects the chance of success with IVF
treatment is the reason why the couple are having IVF in the first place. So, for example,
if the woman is perfectly healthy and the only problem is with the man's sperm, she
will have a better chance of success than a woman who's had complex gynaecological problems
and maybe previous surgery. An example of this would be a woman who'd had complex surgery
for endometriosis. If the couple find if the woman finds that as she gets older the IVF
treatment is not working, there's then always the option to look at donor egg IVF treatments
and with a young healthy donor, success rates with donor egg IVF treatments are very good
and this is reflecting the age of the egg donor rather than the age of the woman who
is the recipient. Success rates overall in the up to 35-year age group are approaching
50%, but with increasing age, the success rates decline and after 40th birthday, success
rates, well, twenty percent would be the upper limit in terms of the chance of success. If
we look at success rates with intrauterine insemination treatments, these are never as
high as with IVF treatment and typically success rates will be in the ten to fifteen percent
bracket, sometimes a little higher than that. So, with the IUI treatment, it's better to
think of it in terms of a course of treatment rather than a single treatment cycle.
Overall, assisted conception treatments are very safe and there are actually very few
risks associated with treatment. A particular concern has been the increased number of multiple
pregnancies. Many couples will view a twin pregnancy as a bonus and that's quite understandable.
However, when we look at twin pregnancies overall compared with singleton pregnancy,
they are more prone to complications. So ideally what we want with a twin pregnancy is two
healthy babies and a healthy mother, but occasionally the outcome is not as we'd wished. An easy
fact to remember is that on average twins are born a month earlier and weigh a kilo
lighter than their singleton counterparts. Because of the risks associated with multiple
pregnancy, there's been a move over the last-- well, more than ten years now to transfer
fewer embryos. This initially started in the Nordic countries and then spread to Europe
and Britain and subsequently the United States. So increasingly now we're just transferring
one good quality embryo rather than two and this is to reduce the chance for a twin pregnancy.
Another complication with IVF treatment which is uncommon but it's important and this is
ovarian hyperstimulation syndrome when the ovaries over respond. Because of the risks
of OHSS as it’s abbreviated to, we're now more cautious about how we stimulate ovaries
and this particularly applies to women with polycystic ovary syndrome. Other complications
from IVF treatments are quite rare. This might be bleeding at the time of the egg collection
or following the egg collection with an enlarged ovary. This can undergo torsion requiring
an operation to untwist the twisted ovary.