Thursday, February 28, 2008

Morphology. What does it mean?

We were told we had a morphology issue since we came in at 10% strict morphology based on the Kruger scale. My RE told us our 10% had cut our chances at a natural conception in half, but since there were good numbers, it wasn't dire or anything like that.

In looking at information about the acceptable ranges for morphology, I've run across many different numbers. I just read "Strict Morphology (Kruger Test) For Sperm Function" and now completely understand what the numbers mean.

"The strict morphology of the sperm predicts a man's fertility potential (fertilizing capacity) even in cases where the sperm count, motility and/or regular morphology of the SA are normal." Due to the very strict rules, "relatively few sperm are rated as 'normal' or perfect during this test, as compared to the 'estimated crude morphology' done during a regular semen analysis (WHO criteria)."

To sum it all up, here is what the numbers mean:

~WHO criteria of regular s/a looks for at least 30% normal sperm. The tests aren't that strict, so many more sperm are considered "normal".

The strict Kruger test looks much, much closer:
~ strict morphology score over 14%: Normal; fertilizing capacity excellent.
~ strict morphology score 4-14%: Abnormal; possibly decreased or impaired fertilizing capacity.
~ strict morphology score 0-3%: Abnormal; severe impairment or probable inability to fertilize.

I'm really glad I found this breakdown. I've seen some websites say that anything over 4% on the strict Kruger test is "normal" and it's not. My RE's determination now makes sense. If I look at 10% being between the lowest "normal" level of 14% and the lowest level of "abnormal" but acceptable of 4%, I see that it really does decrease our chances by 50%! Actually, 9% would be the mark where fertility was decreased by 50%, but it's pretty close.

Bummer. We've got a bigger morphology problem than I had first thought. When I first saw 10% and saw that 14% was what they looked for, I was like "no big deal! We're only 4% away!" But we're not. We're 50% decreased fertility. IVF is looking like the smarter choice a little more each and every day.

NOTE: This is all still a huge numbers game. Someone with 2% morphology and 200 million sperm is going to be "better off" than someone with 14% morphology and 5 million sperm. This post is simply discussing how when dealing with small percentage points where 14% is the top and 4% is the bottom, a few points mean a lot more than my first glance.


Kim said...

I agree, numbers game.

DH had 3% morphology (Kruger), but a VERY, VERY high count, even after motility was considered. If he didn't have that high count, we wouldn't have even bothered with IUI. My RE (who I will not recommend or use again) didn't really seem to care about it at all and only said that Kruger is SO STRICT that it can possibly eliminate sperm that could potentially fertilize and that if he was at 4%, it would have been 'normal'. Whatever. Not a fan of his anyway. Since DH's abnormalities all seemed to be of the same type, I'm pretty convinced it's an actual issue. Whether it's a varicocele or not didn't really matter to us, because the rate of correction after surgery is so minimal and we didn't want to waste time. I did all of this math way back then, so you can read back in September if you want to.

Chas said...

All very interesting. Since we had no sperm (without surgical assistance), I never got to the point where we even considered motility or morphology.

nancy said...

Kim- yes, I agree. Except for the little caveat that 4% is considered "abnormal" but still acceptable. You guys were able to beat it exactly as I because of the reason I talked about - high numbers.

Don't worry, I don't need to go back to your math, I remember it all quite well. It was you I was thinking of when talking the "numbers game".

KatieM said...

I hate Kruger ;-) It freaks me out, because now I'm thinking our chances are MUCH lower than we originally thought. I really think last time was pure luck....not so sure it will happen again.

nancy said...

Katie - What was the count?

As you can see from Kim's comment (and you may remember her story), they had a terrible "3%" too (I'm assuming that is what you said you guys had? Or even a 4%?) but her hubby has incredible high numbers - a nice 200 million for total count. With his 67% motility (i had to go back and look for these numbers) and only 3% morphology, the calculator she used, still showed him having 10.2 million functional sperm.

It's funny. At the time she was SO upset because she thought it was so sucky, but a very short 2 months later she got that elusive BFP after ~ONLY~ TWO IUIs!!!

Remember - don't let the morphology (or motility) get you down when there are high counts. It's all a numbers game.

KatieM said...

Nancy, if I remember correctly Thomas count was 60 mil/mL, with 168 mil. total sperm. All in all I *do* think we are fine, this is just the one issue that is lower than "normal" so I am trying to find blame in something as to why we have IF and for the m/c. Unexplained everything is beyond frustrating.

Plus, even with this, it doesn't make me hope any less for my upcoming least right now.