When to start antagonist ivf
When should the antagonist be started in an IVF cycle ?
hello I'm doctor Anil gory and valo
consultants and reproductive medicine
surgery an assisted conception and
Homerton Fertility Center and today I'm
going to talk to you about the use of an
antagonist we have traditionally
believed that you start antagonists
between a 5 day 6 day 7 started if on a
fixed protocol rather than on a flexible
protocol and that is what the earlier
metallus analysis that showed that a
flexible protocol would give poorer
results in the past many years we have
got better at the Antechinus protocol
our cycles are safer have equal success
rate and we have lowered the risk of
ovarian hyperstimulation now let's have
a look at how different studies are
coming the question is when do you start
the antagonist now this is very much a
retrospective analysis and not a
randomized controlled trial but gives us
an idea into what's going on with the
large number of antagonist cycles which
have been done and this was looking at
cycle day estrogen levels lead follicle
count analysis of over 27,000 cycles
which to decide the optimal start date
of an antagonist and this was published
in April 2018 infertility the criteria
when to start the antagonist was not
standardized it was a retrospective
cohort study from 20 centers 55% had
observations on lead follicle size
extrusion and the start of the
antagonist and what did you see have a
look at the graph it showed that the
maximum pregnancy rates were achieved
when the antagonist was started with a
lead follicle being between 14
and 15 on nine millimeter again the day
of stimulation around day six of
stimulation an extrusion of between 500
to 599 picogram per liter if you start
an antagonist after follicle size was 16
millimeter pregnancy rates dropped by
25% if you started before day 5 or after
day 8 pregnancy rates also declined
fertilization was highest when the
extrusion was in the optimal range
estrogen seems to be an independent
predictor of success rates in this study
but the under gonna start there are very
high levels of Ito also demonstrated
that there could be lower weight babies
the later you start the antagonist you
may lose the receptivity window and also
if you start the antagonist very early
when the extrusion is very low it may
affect the mitotic activity or
follicular cells again this is all
presumption and that is what they the
authors are doing is they're saying well
why is it that the pregnancy could be
lower if you started earlier or we
started later why do the pregnancy rates
start declining at the end this is a
very large sample size 44 percent did
not have adequate details but it tells
us few things in an antagonist cycle if
you want to fine tune your success rates
look at the cycle day look at the
follicle size look at the e2 levels
these should not be ignored so even
though this study is a very large
retrospective data it starts getting us
thinking are we all right to just use
one fixed protocol or should we start
managing and if you start looking at
some of the protocols which I use
especially one which
it looks at poor responders you'll see I
start using protocols that delay the
start of an antagonist using different
drugs and what it allows us to do is
allows us to allow follicle growth to
occur whether or not this can stand the
test of research I don't know but
sometimes our personal observations do
suggest that we may see a better
pregnancy rate anyway thank you very
much if you like these videos please
share them let this knowledge flow these
are reviews of papers which I do once or
twice a week between me and my team
thank you very much
bye-bye
