Tuesday, July 5, 2016

Prenatal ultrasonography

During this time obstetrical sonography went from a medical oddity to a test of such great value that several European countries perform at least two obstetrical sonograms on every pregnant woman and 70% of modern American mothers have had a sonogram during their pregnancy. Obstetrical sonograms provide a wealth of useful information to the primary caregiver. Some of these benefits are easily measured: accuracy of estimating menstrual age, accuracy of predicting twins, etc. Others are more difficult to measure but we all agree are nonetheless of great benefit. One of the most important of these is providing "reassurance" to the expectant mother…

Personally, the opportunity to say, “everything looks fine” to an expectant mother was one of the perks of my job. I can see the wave of relief wash across her face. It’s always a touching moment followed by “thank you, Doctor.” Today, I no longer feel that way. There is a growing number of patients to whom I dread having to speak. I have reviewed the sonographer’s scans and they disclose a finding that will send the mother into a tailspin of confusion and worry. I'm not talking about holoprosencephaly or bilateral renal agenesis. I have a great deal of experience discussing such devastating diagnoses with pregnant women. And while the news is sad, I always feel that I am providing the family with a great service. Nothing can change the fact that her fetus has a mortal anomaly. There will necessarily be a grieving period and tears will undoubtedly flow, but beginning that grieving period at the earliest possible date in her pregnancy is “good medicine.”

Tomorrow when I return to work the odds are I will have to speak to a mother-to-be about an “abnormality” that I see on her sonogram and I won’t know what to tell her. I am talking about “abnormal” findings on her sonogram which loosely fit under the general heading of ”Down syndrome markers” (some are actually better as markers of other trisomy syndromes). I am not referring to atrioventricular canal or duodenal atresia. These are strong indicators that the Down syndrome may be present. But Down syndrome or not, the fetus still has a serious anomaly, and the detection of that anomaly is a benefit. What I am afraid to encounter tomorrow is an “abnormality” which is not really abnormal: choroid plexus cysts, echogenic intracardiac foci, mild pyelectasis, and echogenic bowel. If her fetus has one of these “abnormalities” but doesn’t have the Down syndrome, then her fetus is normal. Excuse me, I’m certain I will be criticized if I don’t tell the mother-to-be that in the absence of the Down syndrome and the presence of echogenic bowel she must worry about her fetus having cystic fibrosis, developing intrauterine growth restriction, having a premature birth, a fetus with a cytomegalovirus infection, or a fetus who may die in her womb. Alternatively, if her fetus has mild pyelectasis and a normal karyotype, her newborn child is at risk for urinary tract problems, must take antibiotics after birth, get an extensive and uncomfortable work-up for vesicoureteral reflux, and be followed up for many months to ensure normalcy…

Unfortunately, the physician performing a routine sonogram and finding one of these “markers” is hard pressed to make a determination regarding which expert to believe. Inevitably they choose the “safest” path; at least, “safest” from a medicolegal perspective. The mother is simply going to have to deal with the possibility that her fetus may have the Down syndrome or something worse…

The researchers who originally described these findings did so in women at high risk to have a fetus with the Down syndrome. These were pregnant women older than 35 years or who had a positive “triple marker” screening test for the Down syndrome. In this group of women the application of these findings increases the probability of finding Down syndrome fetuses, and they perform admirably in this regard. However, these women have already been counseled that amniocentesis is appropriate in their case. They are having a sonogram in order to downgrade their risk to a level where they may appropriately forgo amniocentesis...

But then investigators (with the best of intentions, I am certain) appear to have taken a misstep. These findings, when seen in a woman with a low risk of having a Down syndrome fetus, were used to upgrade her risk. The consumers of this information, the physicians in the trenches, read these scientific papers and then identify these “abnormalities” during a routine sonogram. What are they to tell the patient? This woman hasn’t already been counseled. She is having a sonogram for “reassurance” (forget that now). Her husband, children, and parents are with her. There is a party atmosphere. The videotape is rolling. Soon the giggling and finger pointing at the screen will cease. The questions will change abruptly from “is that the heartbeat?” or “is that the penis there?” to “are you saying that my child is going to be mentally retarded?”

Without doubt you have now added cost to the management of that pregnancy. The patient may choose to undergo amniocentesis. She may be referred to a prenatal diagnostic center for a detailed fetal sonogram and genetic counseling. The innumerable hours of counseling by primary caregivers and general sonologists to explain the “meaning” of this finding are not counted in these additional costs. Nor are the heartaches of the parents-to-be counted in this cost analysis. If they forgo the amniocentesis (clearly the correct choice, in my opinion), then they must live with residual doubt for the remainder of the pregnancy. Does my fetus have the Down syndrome? Maybe I should have had the amniocentesis. The enjoyment of the anticipation of the birth of their son or daughter is now replaced by anxiety…

Possibly I am the exception (I doubt it), but I don't see "all the good." I am a simple-minded physician. I like it when a sonographic finding passes the “Thank God Test.” The Thank God Test is passed when I say to myself “thank God” for that finding. If I hadn't seen it, I would have completely missed this devastating abnormality. I have no instance in my recollection where one or the other of these abnormalities was the sole reason I was able to recognize a fetus with the Down syndrome in a low risk patient…

Obviously someone has had such an experience; just not me. From my vantage point the identification of these “abnormalities” in low risk women has crossed the line of “more harm than good”…

Think about it! For the tiny residual number of Down syndrome fetuses that may potentially come to light by chasing down every last “marker” we intend to put at least 10% of all pregnant women with perfectly normal fetuses through a great deal of worry. So then, what should I do tomorrow? Should I have the courage of my convictions and simply ignore these features? I wish I had that courage, but I don't. Even with my considerable “clout” in the world of obstetrical sonography, I cannot unilaterally ignore the sonographic medical literature. That is not how American medicine works. I am confident that I am not alone in my concerns regarding this issue. I further believe that the authors who did this excellent research in the “high risk” population are becoming aware that these features are not proving as beneficial in the “low risk” population as they had hoped.

Filly RA. Obstetrical sonography: the best way to terrify a pregnant woman. J Ultrasound Med. 2000 Jan;19(1):1-5.
Courtesy of Welch HG.  Overdiagnosed: Making People Sick in the Pursuit of Health.  Beacon Press, 2011.
Inspired by a fetal ultrasound on my wife carrying a perfectly healthy fetus with choroid plexus cysts.


  1. On the basis of evidence-based medicine, the following recommendations and conclusions can be made:

    1) Approximately 60% to 70% of pregnant women have a medical indication for sonography as recommended by the NIH.

    2) Routine sonography in residual low-risk pregnant women does not decrease perinatal morbidity and mortality.

    3) Routine sonography in low-risk pregnant women does not result in fewer unnecessary obstetric interventions.

    4) Routine obstetric sonography has the potential to decrease neonatal mortality if the rate of anomaly detection exceeds 35%, provided that parents subsequently elect pregnancy termination for fetuses with severe anomalies.

    5) The focus of routine sonography needs to be shifted toward optimizing the rate of fetal anomaly detection. To accomplish this, the following would be necessary:

    a) Pregnant women requesting sonography to assess fetal normalcy should ideally have a midtrimester (18- to 20-week) examination by a highly experienced sonologist in a recognized clinical center of excellence.

    b) The fetal anatomic survey needs to be more comprehensive than currently prescribed by ACOG and the AIUM. In particular, the examination should include more detailed assessment of the fetal heart, extremities, and face.

    Filly RA, Crane JP. Routine obstetric sonography. J Ultrasound Med. 2002 Jul;21(7):713-8.

  2. In 2014, usage in the U.S. of the most common fetal-ultrasound procedures averaged 5.2 per delivery, up 92% from 2004, according to an analysis of data compiled for The Wall Street Journal by FAIR Health Inc., a nonprofit aggregator of insurance claims. Some women report getting scans at every doctor visit during pregnancy.

    But medical experts are now warning that frequent scans in low-risk pregnancies aren’t medically justified. A joint statement in May 2014 from several medical societies, including the American College of Obstetricians and Gynecologists, calls for one or two ultrasounds in low-risk, complication-free pregnancies.

    “Ultrasonogram should be used only when clinically indicated, for the shortest amount of time,” the statement said, referring to ultrasound scans, “and with the lowest level of acoustic energy compatible with an accurate diagnosis.”…

    Experts in fetal medicine have long recommended women undergo one ultrasound around the 20th week of a low-risk pregnancy, and in recent years they have come to recommend an earlier one as well, around the 12th week. About 80% of pregnancies are low-risk.

    But in the 2014 statement, doctors and other scientists codified that standard of one or two ultrasounds. And even those involved in the publication of that protocol aren’t sure many obstetricians are aware of it. “Some doctors don’t read medical journals,” says Dr. O’Keeffe…

    Some animal experiments have suggested ill effects of ultrasound on embryos of mice and chickens. And multiple fetal ultrasounds can raise false alarms, including overestimation of fetal size that can lead to potentially unnecessary caesarean deliveries. “Increased use of prenatal ultrasound scanning may be contributing to the rising CD [caesarean delivery] rate,” said a 2012 paper in the American Journal of Obstetrics and Gynecology…

    Now, some fetal-ultrasound experts say women should be explicitly told that—in the absence of complications or alarms—one or two is sufficient for the average low-risk pregnancy.

    “The message needs to be gotten out,” says Phillip J. Bendick, an ultrasound scientist and editor of the Journal of Diagnostic Medical Sonography. “The public needs to be made aware that if you’re pregnant, you don’t drink alcohol, you don’t smoke and you don’t need to have an ultrasound at every doctor’s visit.”…

    The benefits of ultrasounds are proven. They provide a more accurate estimate of when conception began than traditional methods, helping doctors determine when to induce labor when a pregnancy has gone on too long. They can identify multiple fetuses and detect abnormalities that elevate a pregnancy’s risk level. In high-risk pregnancies, additional scans often are crucial.

    And research suggests images of the unborn can help foster bonding, perhaps persuading some pregnant women to quit smoking…

    Research suggests multiple scans don’t provide better outcomes in pregnancies. A study in the journal Lancet in 1993 set out to prove the superiority of five fetal ultrasounds over one, but it found no benefit to additional scans. “Routine scans do not seem to be associated with reductions in adverse outcomes for babies,” concluded a 2010 analysis of published literature on fetal ultrasound, by the medical-research nonprofit Cochrane Collaboration.

    And fetal ultrasound sometimes produces false positives, requiring additional scans to rule out problems that never existed. The 2012 American Journal of Obstetrics and Gynecology paper found women who received a fetal-weight estimate via ultrasound within a month of delivery were 44% more likely to be delivered by caesarean section.

    “If you go looking for trouble,” Duke’s Dr. Kuller says of unnecessary scans, “you will find it.”


  3. IF I had been paying more attention, I might have noticed the plaque outside the room that the obstetrician was ushering us into: Patient Education. And had I noticed, I almost surely would have been alarmed. I was 20 weeks pregnant with my first child and had just had a ''routine'' ultrasound examination. What did I need to be educated about?

    But I did not notice, and I was not anxious or on guard. I had enjoyed the sonogram. Expectant parents do. It is a bonding opportunity. It is baby's first video. I had already had amniocentesis several weeks earlier, to check for chromosomal abnormalities associated with so-called elderly gravidas like my 38-year-old self.

    I knew that my baby had 23 neatly matching pairs of chromosomes, that her spinal tube had closed and that she did not have a gruesome defect like anencephaly -- no brain -- that would propel me to have an abortion despite having struggled for years to get pregnant.

    In sum, I knew my baby was healthy and magnificent, and had gone into the ultrasound expecting added proof of her splendor.

    The obstetrician began discussing the scan results. Her tone was hesitant, clipped, distinctly not the voice of reassurance. A siren of panic began wailing in my skull. She said this was fine, that was fine, blah, blah, blah. Come on! I thought angrily. Get to the point! What's wrong with my baby?

    Finally, the doctor came to the problem. The left foot. She said the results were difficult to interpret. The foot was in a funny position in the uterus, crammed down deep in the pelvis, so it could be simply a matter of its position at the moment. But the sonographer had not been able to see the profile of the foot, no matter what angle she came at it from, and that is what happens when you have a clubfoot. My husband and I looked at each other in dumb, grim shock. Clubfoot? Neither of us was sure what a clubfoot was, what it looked like or how bad a defect it was. The term was so thuddingly ugly and Dickensian that we could not help imagining the condition must be ugly and severe.(continued)

  4. (continued) The obstetrician told us we had a couple of choices. We could go to a university facility for a more in-depth sonogram, or we could just do nothing and go on with the pregnancy. A clubfoot would not affect the course of the pregnancy, she said, and any effort to correct it would have to wait until after the baby was born.

    Oh, sure, do nothing and forget all about it -- that is a realistic option, I thought bitterly. Thus we started down a rutted path trudged by so many tens of thousands of people each year, that of medical testing and retesting, the contemporary version of consulting the Oracle of Delphi or a platter of entrails. It is a path that is getting bumpier and more perilous by the month, as ever more high-tech assays are added to the list of prognostic options…

    Among them: How do you interpret equivocal or confusing results, and how does a patient react to a test's inherent uncertainty? What do you do -- what can you do -- with bad news once you have received it? Most important is the taint of eugenics surrounding many of these screens: How perfect must a person be to deserve health insurance, a job, a parent's love, or life itself?

    Leaving the obstetrician's office, my husband and I headed for a medical library to do research on clubfoot. The pictures in textbooks were devastating. Some of the feet were extremely deformed, bent in and up at the ankle to form the letter J. Toes and heels were bunched and twisted. The feet were often stunted, and the calves of the clubfoot leg were comparatively underdeveloped…

    That night, my husband and I did not sleep at all. We wept and wept. Privately, we each pleaded with the universe to make the follow-up sonogram come out normal. We offered up our own body parts in exchange: eyes, arms, feet.

    The universe was deaf. The next day, a doctor at a nearby university hospital concurred with the preliminary diagnosis of clubfoot, subtle though the evidence was. ''Good catch!'' he said admiringly of the previous sonographer's work.

    In the car ride home, I howled so hard I thought the sky would crack; but the sky stayed whole and calm and blue…

    I read of famous clubfooted figures in history and literature: Lord Byron, Goebbels, the town simpleton in ''Madame Bovary'' whose leg had to be amputated after Dr. Bovary tried unsuccessfully to treat the deformity. But I also spoke to mothers of children with clubfeet and was inspired by their stories. They assured me the casts in no way slowed their children down or interfered with motor milestones like crawling. They said that with their feet fixed, the children could walk and run with the best of the nonclubbed masses. Finally, toward the end of my pregnancy, I began to relax.

    In late August, I gave birth to a healthy daughter with a lusty set of lungs, a full head of black hair -- and no clubfoot at all.


  5. The use of ultrasound scanning during pregnancy is now so widespread it seems almost as banal as taking a patient's blood pressure. Unlike amniocentesis, it is considered safe, noninvasive and painless for both mother and child. Formal studies indicate that 70 percent of all pregnant women get at least one scan, and the true number is probably higher, said Dr. E. O. Horger 3d, chairman of obstetrics and gynecology at the University of South Carolina School of Medicine in Columbia. If a woman does not request ultrasound, many obstetricians will recommend it, as mine did, ''just to see how things are going.'' They make that suggestion even though the American College of Obstetricians and Gynecologists, the American Academy of Family Physicians and other medical organizations advise against the routine use of ultrasound in pregnancy.

    These groups emphatically favor ultrasound when there is medical justification, for example, if the woman begins bleeding or may be carrying twins. But they see no benefit in laissez-faire scanning when the pregnancy is going fine.

    Behind that position are the results of a large clinical trial called the Routine Antenatal Diagnostic Imaging with Ultrasound, or Radius, study, published in The New England Journal of Medicine and elsewhere in 1993. In that study, 15,151 women with low-risk pregnancies were randomly assigned to one of two groups. The first received routine ultrasound examinations in the second and third trimesters, while the other group received no sonograms unless there was a problem, like bleeding.

    The study found no benefit from routine screening. Ultrasound did not reduce the number of infant deaths during delivery, nor did it in any way lead to an improvement in the newborn's health. More fetal anomalies were picked up in the screened group, but that early detection had no tangible effect, like an increase in abortions, or better care for the newborns. The researchers concluded that universal ultrasound would add millions of dollars to the cost of prenatal care with no payback in better babies.
    The response to the study was immediate and furious, and continues resonating. ''Among practitioners, those who did not believe in routine ultrasound now feel justified, while the majority of those who did believe in it have attempted to ignore or discredit the study,'' said Dr. Bernard G. Ewigman of the University of Missouri School of Medicine in Columbia, the first author of the report.(continued)

  6. (continued)Much of the harshest censure of the study has come from doctors who excel in ultrasound diagnosis. They criticize the criteria used in selecting the women. ''They excluded those cases that would automatically warrant a scan, like a patient who's not sure how far along the pregnancy is,'' said Dr. John C. Hobbins, director of obstetrics at the University of Colorado Health Sciences Center in Denver. ''By design they narrowed down the study population to the point where it doesn't represent the real world.''…

    False positives like mine are said to be very rare, yet without trying I learned of three other women whose fetuses were incorrectly diagnosed as having clubfeet. And while these mistakes were joyfully resolved, false positives can have devastating outcomes. Dr. Horger cited the case of a woman who received an ultrasound diagnosis that her fetus had no kidneys, a fatal condition. She aborted the fetus at 18 weeks, and an autopsy revealed apparently normal kidneys.

    More often women receive murky results that are difficult to interpret, but that offer just enough substance to nourish anxiety. During several scans performed in her third pregnancy, a neighbor of mine was told that her baby might have a serious kidney defect. There was nothing to do but wait and worry. Months later, she gave birth to a healthy daughter. Another acquaintance, who is still pregnant, was told after a sonogram that her fetus's eyes were unusually close together. She asked her doctors what it meant and what she should do about it. They did not know, and they suggested more scans. She refused. ''So maybe the baby will look like Lyle Lovett,'' she said, maintaining her humor but clearly worried…
    It gives the illusion of perfectability, but like most medical assays, ultrasound is imperfect. It can find problems where none exist, and, more often, it misses defects that exist. More than half of all defects have been shown to go unnoticed by ultrasound. ''The search for the perfect child is making women very anxious about reproducing,'' Dr. Ruzek said. An unfortunate byproduct of expecting perfection is the urge to sue upon arrival of an imperfect baby. Dr. Horger said one of the commonest causes of obstetrical lawsuits is the failure of a doctor to pick up a birth defect on ultrasound. Although the Radius study indicates that early detection of most abnormalities does not do much good anyway, doctors end up screening just to cover their afts…

    A particular problem with ultrasound is that while women know that amniocentesis and most prenatal tests are designed to look for defects, they approach their sonogram with optimism. ''They're persuaded they'll be reassured, and will get their first picture of the baby,'' said Dr. Gail Geller, a bioethicist at Johns Hopkins University. ''But the physician's training is to find something that might be wrong. There's a cognitive dissonance between practitioners and patients.'' Indeed, she said, ''physicians can sound almost excited when they find something.'' That happened to us, with the doctor who murmured appreciatively, ''Good catch.''

    In the end, many researchers said that women should be entitled to have ultrasound and other prenatal tests, but that the process of informed consent must be taken far more seriously than it currently is. Women should be told in detail of the limitations of screening, and of the fact that clinical studies show no benefit to scanning during a normal pregnancy, Dr. Geller said. Nor is it clear that doctors should bother ferreting out every minor aberration -- every cleft lip, every excess finger.


  7. Ultrasound for fetal assessment in early pregnancy does not impact on perinatal death (defined as stillbirth after trial entry, or death of a liveborn infant up to 28 days of age) (RR 0.89, 95% CI 0.70 to 1.12; participants = 35,735; studies = 10, low quality evidence). Routine scans do not seem to be associated with reductions in adverse outcomes for babies or in health service use by mothers and babies.


  8. In 1998 the U.S. Preventive Services Task Force (USPSTF) published a guideline on the use of screening ultrasound in pregnancy. Citing the fact that “neither early, late, nor serial ultrasound in normal pregnancy has been proven to improve perinatal morbidity or mortality”, the USPSTF recommended against routine ultrasound in the third trimester. Additionally, they concluded that there was insufficient evidence to make a recommendation regarding a single routine mid-trimester ultrasound in low-risk pregnancies. These recommendations applied only to routine screening ultrasounds, and not to diagnostic ultrasound for specific clinical indications.


  9. Höglund Carlsson L, Saltvedt S, Anderlid BM, Westerlund J, Gillberg C, Westgren M, Fernell E. Ultrasound in the first and second trimester and autism; a prospective randomized study. Ultrasound Obstet Gynecol. 2016 May 17. doi:10.1002/uog.15962. [Epub ahead of print]

    To analyze whether the frequency of Autism Spectrum Disorder (ASD) differs in Swedish cohorts of children exposed to ultrasound either in the 12th or 18th week of gestation.
    The study cohort consisted of approximately 30 000 children with birth-years 1999-2003, born to mothers, who, within the framework of a study of nuchal translucency (NT) screening, had been randomized to prenatal ultrasound in either gestational week 12 or 18. The outcome measure in the present study was the rate of ASD diagnoses in the children. Information on ASD diagnoses was based on data from the Swedish Social Insurance Agency concerning granted childcare allowance because of ASD.
    No difference in ASD frequency between the early and later subgroup could be detected. A total of 14 726 children were born after early and 14 596 children after later ultrasound in 1999-2003 and of these, 181 (1.2%) and 176 (1.2%) children, respectively, had been diagnosed with ASD.
    Women, subjected to at least one prenatal ultrasound in either gestational week 12 or 18, had children with similar rates of ASD. However, the result reflects the routine used 10 to 15 years ago in Sweden. Today, many and early, higher intensity ultrasound scans are performed during pregnancy and also for non-medical purposes, implying longer exposure time for the fetus. This changing use of ultrasound necessitates further follow-up studies of the possible effects on the developing brain of high exposure to ultrasound during the gestational period.

  10. Mario Sarti A Junior, Okido MM, Araujo Júnior E, Cavalli RC, Quintana SM, Duarte G, Marcolin AC. A structurally normal fetus at the 11- to 14-week ultrasound does not guarantee a newborn without congenital anomalies: a cohort study. J Matern Fetal Neonatal Med. 2016 Mar 3:1-7.

    The objective of this study was to analyze the influence of maternal demographic characteristics and abnormal first-trimester sonographic markers on congenital anomalies (CAs) at birth when the fetus is structurally normal at the 11- to 14-week ultrasound.
    This prospective cohort study comprised high-risk women undergoing routine antenatal care. Detailed assessments of fetal anatomy and first-trimester sonographic markers were performed at 11-14 weeks of pregnancy. Multilevel regression analysis was used to determine the effects of maternal characteristics and abnormal first-trimester sonographic markers on the incidence of CA at birth.
    Three hundred and ten patients were evaluated, and 41 patients (13.2%) had an anomalous newborn. The presence of a specific indication at the first-trimester ultrasound (OR: 2.72; CI 95% 1.09-6.74) or a nuchal translucency (NT) thickness greater than 2.5 mm increased the risk of CA at birth by three fold (OR: 3.10; CI 95% 1.07-9.59). High adjusted risks for trisomies 21, 18 and 13 increased the likelihood of having a structurally abnormal newborn by five, twelve and six fold, respectively.
    Increased NT and/or high adjusted risks for trisomies 21, 18, and 13 increase the risk of CA at birth, even in fetuses with a structurally normal 11- to 14-week ultrasound scan.