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08/04/2003
Outnumbered
After the embryo attains a CRL of 5 mm, the probability of subsequent loss falls to 7.2%. The loss rate drops rapidly thereafter to 3.3% for embryos with a CRL of 6 mm to 10 mm and to 0.5% for embryos with a CRL of 10 mm or more (i.e., 5 weeks postovulation or 7 weeks after the last menstrual period). That 3.3%? That's us.
Only 1.9% of pregnancies have small gestational sacs in relation to crown-rump length.
According to that same study, 80% of pregnancies fail when the difference between MSD (mean sac diameter) and crown-rump length (CRL) is less than 5 mm.
Another study with a smaller sample, however, found a more ominous failure rate: 94%.
Pregnant women have a lot of magical talismans they like to invoke against the potential for loss. One of them is the mythical 5% — "Once you've seen the heartbeat, your chances for miscarriage drop to 5%." There are a lot of things wrong with that statement, primarily the assumption that any statistic pertains to any individual. I am most painfully aware that even if you assume that magic number is accurate, somebody still has to be in that 5%.
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Count me in the .5% as of Monday. CRL was 1.33 cm on June 29, but sonogram on July 18 showed a baby that died a week before. Miscarriage sucks, and percentages and statistics mean shit when you're on the losing end of them.
Your blog, and your strength, have made me smile for the first time in days, however. Thank you.
Jenni, I'm terribly sorry for your loss. I'm glad what I wrote helped you somewhat, but, man, this stuff is hard, huh?
I guess that I can join the club of the 0.5% unlucky. We went in for what would have been our three month appointment to hear the heartbeat, only to spend the rest of the night at the hospital and hearing the horrible words "I'm sorry - your baby doesn't have a heartbeat." Well, two D&C's later (I'm just lucky that way), I am still trying to put the pieces back together. Julie - your blog has really helped me through the past weeks, and I want to thank you for sharing your story. I have been a long time reader, and it helps me to know that I am not alone in this. It helps me to know that other people understand how much this hurts, other people have taken these punches to the gut that they never thought they could surive, and yet, I have watched these people stand up and try again. Although my knees are wobbling, I'm standing up and I have to believe I'll make it.
Jaime, I'm so sorry for your loss. You're going to make it. I have to believe we all will, somehow.
I agree - these numbers are worthless when it comes to an individual. I lost at 10 weeks, after seeing a strong healthy heartbeat. So what good does it do me to learn that I was in that smallest of percentages to whom this happens? None - it only makes it worse, knowing that I had the rarest of miscarriages.