Is there any point in prenatal screening for Cystic Fibrosis?

My midwife gave me a pamphlet about it and told me to decide for my next visit, and I’m thinking no. It’s not something I would choose to abort over, and my husband and I aren’t in the high risk groups anyway. (He’s British and Italian and I’m a Heinz 57 of 1/2 German half everything in the UK, French, Canadian and Native American).

But is there any other reason to find out prenatally? If WhyBaby does have CF, would it be better to know ahead of time so specialists could be on hand at the birth? We’re delivering in a hospital anyway, so they wouldn’t be that far away even if we didn’t know.

And it doesn’t seem as if the test tells us for sure anyway - it just tells us if WhyDad and I are genetic carriers - so what’s the point?

All these tests they can do today! I think it causes more worry in the long run.

You might find this PDF document from the Cystic Fibrosis Foundation useful.

My brother died of cystic fibrosis in 1980 at the age of 9. (I was 12.) He was a great kid but had a painful and difficult life, and of course my parents were heartbroken. Treatment is better today and the average life span is longer (my brother died on the young side; average was about 18-21 in those days), but CF isn’t a condition I’d wish on anyone.

There is a 2/3 chance that I am a genetic carrier. When my wife and I decide to have children, I’ll get tested and if I’m positive, she’ll get tested. If we’re both positive, we’ll probably adopt.

I’m not trying to persuade you of anything, just offering the perspective of someone who has (sort of) been there.

Thanks for the link, I’ll definitely check it out. Since I’m already at 16 weeks, adoption’s not an option for this one. Seems to be it might make more sense to have couples screened pre-pregnancy, not prenatally. If I had reason to believe I was a carrier, through a relative with the disease or through a blood test done when I wasn’t pregnant, I would have looked at other options, too.

Actually, being Caucasian DOES put one in the high risk group. Especially British Isles ancestry. Apparently some folks feel every single Caucasian should be tested for this trait, just as they feel anyone of African ancestry should be tested for sickle cell anemia.

You wouldn’t need specialists on hand at the birth, but if your child did have this condition then the sooner they enter in to treatment the better - the average lifespan of cystic fibrosis sufferers has gone from the single digit years into the 20’s and 30’s because of better treatments.

If you find out your child has CF you have to choices: abort (which you say you won’t do) or raise the kid (which is what you’ll do anyway).

The only advantage I can see for testing is that if neither of you is a carrier, you needn’t worry. If only one of you is a carrier, then you needn’t worry. Only if both of you are carriers can one of your children have CF, and even then, the chances are 1 out of 4.

By the way - I am not a doctor. If someone like Qadgop the Mercotan drops in and contradicts anything I just said please ignore me and believe him. If I recall correctly, his family has some direct experience with this disease.

Interesting. The pamphlet I got says Ashkenazi Jewish descent, but doesn’t mention the British Isles. E. Thorp’s link does say “Caucasian.” So maybe we should be tested. Does the fact that we’re so genetically mixed up help our chances any? Neither of us is more than “half” anything in particular.

Yeah, I’m sort of hoping QtM drops by, but I hate those “Paging Qadgop” threads. They’re so obnoxious and presumptuous.

Ashkenazi Jews seemed to be lumped in with all the genetic tests for some reason - but for them, it’s more usually something like Tay Sachs. I was not aware of them being at unusually high risk for CF.

The fact that you have some non-Caucasian (that Native American you mentioned) would lessen your risk - CF is very rare outside of Caucasian groups (and every other ethnicity you mentioned is Caucasian). But how much your risk is lowered depends on the proportion of Native American you have - if you’re 50% the risk is probably lowered significantly. If it’s your mutiple-great granddad and the rest of your heritage is Caucasian no, it doesn’t make much difference.

However, and I can’t emphasize this enough, the risk of any two randomly chosen Caucasians both being carriers without a family history of the disease is pretty low, even if it is higher than for other ethnicities/races. It’s a possibility, that’s all. This is not something new that’s suddenly popped up in the human race, it’s been around for thousands, if not tens of thousands of years. The vast, overwhelming majority of people, even in the risk categoy Caucasian, do not have the disease and only a minority are carriers. The only difference is that now we can identify the carriers.

You have to decide whether or not to get tested, but ask yourself if knowing the results of this test would make you do anything differently? There’s no treatment pre-birth, if niether of you have relatives with CF, and if you would have the kid in any case I have to seriously ask why bother? What would it change? Have the kid, who will almost certainly be a normal, healthy kid, make sure the tyke has those regular baby check-ups, and don’t go looking for too much trouble.

Now, if you plan to have more children in the future maybe knowing whether or not you’re a carrier or your husband is might affect your decision. I mean, if neither of you carry a copy of the trait you CAN’T pass it on. Even if just one of you has it - it takes a double-dose to cause the disease. Is that peace of mind worth the test? For some, I suppose. The only time you’d really have to worry is if you’re both carriers… but the odds are against that.

It would be nice if a doctor came along with actual odds.

Regardless, DON’T get too worked up about this. They test pregnant women for a lot of things these days, poke and prod and peek. It almost makes one long for the days when no one got a specific due date, no one knew the gender before birth, and no one’s picture album had ultrasound prints in them. The vast, overwhelming majority of babies are born normal and healthy.

There’s some evidence that CF carrier status may have helped provide resistance to the bubonic plague, which could help explain why CF is so much more common among populations of European descent. Kind of like the sickle-cell/malaria thing.

Qadgop and Mrs. Mercotan are both generally Euro-mutt, half Dutch on Dad’s side, a chunk of British on Mom’s. Dad has never been able to find ANY Jewish ancestry, though he’d love to find some to annoy some of his relatives with. And yet the littlest Mercotette has CF, and I’m currently delaying my return home from Canada to make absolutely sure that this flu I picked up doesn’t infect her with anything respiratory.

Anyway, I don’t really know what’s involved with testing nowadays, but my advice to you would be to get SOME sort of testing done very early on in the kid’s life, if not before birth, so that you’ll be able to begin treatment as soon as you need to. My sister was a rather unhappy, stinky little kid before we found out she had CF. (Or maybe the fact that I was four and a half when she was born is clouding my perceptions…)

Oh, something tells me he’ll show. :slight_smile:

well, it’s a good idea if there are indications that CF is present but there’s no need to get worked up if there aren’t. There’s no need to get testing done after birth if you are simply Causasian with no known risks and no symptoms. Obviously once symptoms present, testing is a real fine idea.

I don’t know how I feel about these broad prenatal testing thingies. I do think that if someone is really opposed to raising a child with a particular diagnosis then they do serve a purpose but the lack of specificity with prenatal testing is a worry. But then this week I’m taking my 7 yo for an MRI to rule out occult spina bifida and I’m pretty sure we are going to find it. There’s NO way I would have aborted this child for spina bifida but if a test had shown spina bifida I would have considered it. I wish these tests were more clear about the degree of impairment. I don’t know enough about CF – is it like spina bifida or downs syndrome where there are degrees of it?

OK, here are some stats from the Cystic Fibrosis Foundation:

Approximately 10 million people in the US are carriers - that’s out of what, 280 million people? If you are a carrier you are symptom-free and do not have the disease.

1 in every 3,200 live births to Caucasian parents is a child with CF. One in every 3,900 births overall so yes, being Caucasian IS a risk factor.

Apparently there are some different degrees of the illness - they say that while 80% of cases are diagnosed by age 3, some are not diagnosed until after the age of 18. The site ( claims that there are over 1,000 variations of the CF gene.

Testing is done, apparently, by testing the sweat, which strikes me as a painless and noninvasive procedure.

From MedLine:

Ashkenazai ethnicity is not mentioned (although they are Caucasians of Central European ancestry). But, as you can see, while the gene is most common in Caucasians, at 2-5% of people it’s still a small segment of the Caucasian population. Of that 2-5%, only a small sub-group of that actually have the disease.

You know, about a year ago I saw a recommendation for testing for CF in all pregnancies where at least one of the parents had any Caucasian ancestry. And I thought - this is going to freak a lot of people out. Because most folks don’t really think about or understand risk factors for birth defects and genetic problems until they’re pregnant, which is probably not the best time to be thinking about these things since you’re already emotionally overloaded anyhow.

I also found it vaguely amusing how all these nice, white-bread docs sputtered “but… but… you can’t make being Caucasian a risk factor!” Oh, like it’s OK to say African ancestry is a risk for sickle cell, or Jewish ancestry a risk for Tay Sachs, or Pacific Islander/Native American a risk factor for diabetes, but Caucasians should somehow be exempt?

By the way - in the 1960’s when they came up with a test to determine if people were sickle cell carriers or not it caused quite a ruckus and there was some unpleasent social side-effects from what was intended to be a benefit to prospective parents. (not to mentioning testing focused almost exclusively on sub-Saharan Africans when Greeks, Italians, Arabs, and Indiana (east variety) are also at risk for this, “despite” being Caucasians) I really hope this won’t turn into a repeat. If you’re curious, about 8% of African-Americans carry the trait, and the incidence is even higher in some parts of Africa. Nontheless, there are plenty of healthy folks in that risk group, life goes on, and while it’s a concern it doesn’t stop people from having kids.

We’re all at risk for something. Yes, mixed ancestory probably is a good thing in most cases.

But, frankly, I’m not sure how much good testing for this at 16 weeks would do - at that point you have two choices, abort or have the kid. And if you’re going to have the kid regardless, and there’s nothing you can do before birth, why do another test? Does knowing before birth somehow improve the outcome over, say, diagnosing at three months? If it was discovered that both of you were carriers there is STILL only 1 chance in 4 the child will be affected, and you’d STILL have to wait until after the kid is born to test the kid, right? And even if you could test the tyke before birth, could it even indicate how much the kid will be affected? Don’t parents have enough to worry about?

If the docs are pushing this ask them how this test will benefit YOU or YOUR CHILD which you say you will have regardless of how a test comes out. I’m not saying this is the case, but sometimes docs seem to want to test just because they have a test, not because it will really make a difference.

:smack: east INDIA, not INDIANA!!!

Clearly, there is too much blood in my caffeine-stream this morning…

I recall seeing public service announcements on TV a number of years ago urging parents to kiss their babies (as if most need encouragement!) and if the baby tastes salty all the time to have them tested for CF.

My niece was tested as a baby for CF because she had constant coughing and wheezing, lots of lung infections, ate lots and never gained weight… and it turns out she had really bad asthma and not CF at all. Regardless of what tests say, you still have to watch your kid for symptoms. If they’re healthy try not to worry too much. If they’re not healthy, take them to a doctor.

It certainly is - you can’t test for everything, and none of those tests is 100% accurate so in those cases you risk aborting a healthy baby. And like I said, aside from a very few conditions there’s nothing you can really with that knowledge except abort. The list of conditions that can be treated pre-natally or at birth is pretty short. Rh factor disease is one - knowing that ahead of time can be life or death for a baby, but it’s a simple blood test for the parents and it’s been around for decades. There have been some attempts to perform surgery on babies in the womb, but those conditions where it could make a difference are pretty rare and the results somewhat hit-or-miss (not to mention there are risks to both mother and child).

I think sometimes the constant testing causes more anxiety than it relieves.

Well, gee, things have improved for kids with spina bifida - when my husband was born 47 years ago he was given a life expectancy of 6 weeks and several of his relatives seriously proposed drowning him in the river (seriously - a couple of 'em volunteered to relieve his parents of the chore). He does have problems from it (it wasn’t “occult” at all in his case) but he’s upright, walking without assistance, and of above-average intelligence. It pisses me off when people get news their baby has something like this and immediately they’re deluged with worst-case scenarios and busy-bodies who suggest a flush-and-start-over approach to child-bearing. Yes, abortion is justifiable in some instances but too many people these days seem to willing to suggest the idea as a first choice instead of a last resort.

Oh, don’t get me started…

WhyNot, are you finding this reassuring or more upsetting? If this isn’t helping I’ll shut up and go somewhere else.

Reassuring, actually. My process is to gather lots and lots of information and opinions from people who know more about a topic than I do. Then I sift through it and figure out what I think about it and what I’m going to do. I don’t have a problem hearing about bad things in theory - I actually don’t mind reading* What to Expect When You’re Expecting*! (But I don’t want it to be my only source of information, either.) One of my dads is a pharmacist in a neo-natal intensive care ward of a children’s hospital, so I hear all sorts of horror stories of what can go wrong with the baby making process. It’s made me fairly pragmatic about the whole thing.

The midwife is being completely cool about it being an option, but not pressuring us either way.

(It’s also interesting finding out more about the signs and symptoms of CF, because my brain immediately starts translating them into a Chinese Medicine diagnosis and thinking of dietary, herbal and acupuncture treatments. The result: ick. Not something I’d want to treat! But that’s neither here nor there.)

I feel like I should address everyone, but I’m not sure where to start. So let me just say thank you all for your input. Please, if there’s anything else or anyone else, keep it coming. Personal experience, phsycian knowledge or just general opinions are all welcome

Information on prenatal testing for cystic fibrosis:

NIH Consnsus:
Genetic testing for CF should be offered to adults with a positive family history of CF, to partners of people with CF, to couples currently planning a pregnancy, and to couples seeking prenatal care. The panel does not recommend offering CF genetic testing to the general population or newborn infants.

Overview on cystic fibrosis:
Like any medical test, a decision should weight the risks, benefits and how it would change management. It makes sense to test people highly concerned about CF (due to history, family history, etc.). Testing with sweat chloride is easy. Testing with amniocentesis or chorionic villi sampling in situ is not without risks – up to 0.5-2% abortion rate. Would a positive test change what happens next?

Dr_Pap, MD

Over 1000 mutations in the CF gene that contribute to the disease state have been identified. In order to have the disease, you need two mutations - nearly always, one from each parent. Since sequencing the whole gene is quite expensive, usually genetic testing is done on a panel of about 32 of the most common mutations, which should pick up well over 90% of carriers in the Caucasian population.

True, once the baby’s born. But you can do genetic testing prenatally on amniocytes.

Anyone undergoing this type of testing should be given access to a genetic counselor who can explain the issues involved.

As I said, you can test the baby before birth, but no, knowing which mutations are present doesn’t give you a good idea of the eventual severity of the disease. There are a few exceptions - certain mutations in certain combinations are associated with certain symptoms, like CBAVD (the congenital absence of the vas deferens).

(We do a lot of CF testing at the lab where I work.)

My take on the OP as a doc and a CF dad is that unless you’re gonna abort if the test is positive, screening may not be necessary. If the kid fails to thrive, or has trouble early on, CF can be tested for then.

Just an opinion.