Wednesday, April 21, 2010

Science speak


Ok, so I spoke to the IVF clinic scientist today who ran me through my freeze record.

What an inordinately bizarre sentence that was.

That's what my little list of chilly embryos is called apparently: a freeze record.
So, up until this afternoon when I had a 20-minute chat with the scientist, I had thought of those seven frozen embryos as fairly equal in vitality.
Now, I know a bit better.
Apparently the scientists grade them and the average is Grade Two (Three is the best, and rarely bestowed, the equivalent of a Nobel Peace Prize in embryo world).
They also then like to only freeze the ones that show a division of more than two cells, at least, by the time a few days have passed after fertilisation.
And mine are all Grade Twos...and among them are three two-cells, two three-cells, one four-cell and one five-cell.

They will thaw the five-cell first and then progress down the line, if need be.
See, the thing is, there is a 70-80% survival rate in the thawing process. That's a good stat, in my book.

Some do not continue to divide, some show some lacerations or irregular cell development...and it just doesn't work.
But the scientist did say the "vast majority" continue to divide. A good stat.
I asked her what the difference was between pregnancy success in fresh versus frozen embryo transfers.

Apparently for someone my age, there is a 40% chance of getting pregnant with a fresh embie, and a 30% chance if I go frozen.
But she did say that rate is always going to be less because the very best embies - the pick of the bunch - are put in first, and fresh. So, grain of salt.

Still, whether you're talking about 30 or 40%, it doesn't sound very high, does it? Bad, bad stat.
But despite the differences in success rates in fresh versus frozen, the fact is pregnancies do result from frozen transfers every year...all the time.

I finished off our informative conversation by telling her that perhaps it was an occupational hazard thing that demanded I be so questioning and over-informed (I'm a journalist).
And I do feel more reassured knowing more than I probably need to...perhaps.
Yes, I do.

The uncertainty was beginning to niggle.
Beginning to?
Who am I kidding.
It always has.

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