The development of obstetric ultrasound in Switzerland

Ultrasound has conquered obstetrics during the last 40 years. Today it is an integral part of antenatal care. Its broad use as a screening method has pushed critics who found open doors at health authorities facing short resources. In Switzerland in early 1996, routine ultrasound as a health technology was temporarily excluded from reimbursement by the health insurances. Under the pressure of the public, the health authorities had to reintroduce reimbursement within a few months. However, reimbursement was linked with several conditions: the ultrasound examination has to be performed by physicians with adequate training and experience; routine ultrasound needs a strict informed consent, and its benefit has to be evidenced. This decision has had a positive impact on quality. After 7 years, Switzerland has a good training program; guidelines for prenatal ultrasound already exist in their second edition, and spot checks of performance showed that quality in Switzerland meets international standards. Ultrasound mainly has a positive cost-effectiveness ratio due to the detection of fetal malformations with consecutive termination of pregnancy. Since termination of pregnancy is ethically questionable, the discussion with respect to reimbursement will most probably go on. In this light, a comprehensive informed consent of the pregnant women is essential.     

Women's Views of Pregnancy Ultrasound: A Systematic Review

ABSTRACT: Background: Ultrasound has become a routine part of care for pregnant women in most countries with developed health services. It is one of a range of techniques used in screening and diagnosis, but it differs from most others because of the direct access that it gives parents to images of the fetus. A review of women's views of ultrasound was commissioned as part of a larger study of the clinical and economic aspects of routine antenatal ultrasound use. Methods: Studies of women's views about antenatal screening and diagnosis were searched for on electronic databases. Studies about pregnancy ultrasound were then identified from this material. Further studies were found by contacting researchers, hand searches, and following up references. The searches were not intentionally limited by date or language. Studies that reported direct data from women about pregnancy ultrasound were then included in a structured review. Studies were not excluded on the basis of methodological quality unless they were impossible to understand. They were read by one author and tabulated. The review then addressed a series of questions in a nonquantitative way. Results: The structured review included 74 primary studies represented by 98 reports. Studies from 18 countries were included, and they employed methods ranging from qualitative interviewing to psychometric testing. The review included studies from the very early period of ultrasound use up to reports of research on contemporary practice. Ultrasound is very attractive to women and families. Women's early concerns about the safety of ultrasound were rarely reported in more recent research. Women often lack information about the purposes for which an ultrasound scan is being done and the technical limitations of the procedure. The strong appeal of diagnostic ultrasound use may contribute to the fact that pregnant women are often unprepared for adverse findings. Conclusions: Despite the highly varied study designs and contexts for the research included, this review provided useful information about women's views of pregnancy ultrasound. One key finding for clinicians was the need for all staff, women, and partners to be well informed about the specific purposes of ultrasound scans and what they can and cannot achieve. (BIRTH 29:4 December 2002)     

Revelations: A Summary and Analysis of the NIH Consensus Development Conference on Ultrasound Imaging in Pregnancy

ABSTRACT: The Consensus Development Conference on Diagnostic Ultrasound Imaging revealed that neither the energy emitted from an ultrasound transducer, nor the energy absorbed by maternal and fetal tissues has been quantitated. For convenience, the energy is expressed in watts/square centimeter. Although in vitro and animal studies have shown various bioeffects of ultrasound, none obtained under 100 mW/cm² has been reproducible, and none can be translated reliably to humans. Four randomized controlled trials of ultrasound imaging failed to show harmful effects, and also failed to show benefits of routine screening in terms of infant mortality or morbidity. The panel accordingly recommended that ultrasound imaging be used only with a specific indication, and listed 27 indications. They recommended that women be supplied with information about exposure time, intensity, indication, alternatives, and benefits and risks of an ultrasound scan, if they request the information. The panel also recommended further research on outputs, bioeffects, and efficacy of routine screening by ultrasound during pregnancy.     

Controlled Trials of Routine Ultrasound in Pregnancy

ABSTRACT: It is uncertain whether the evidence of randomized controlled trials justifies extending diagnostic ultrasonography for specific indication to routine screening in early and late pregnancy. The five such trials analyzed here show different inclusion criteria, outcome variables, trial reporting, and use of ultrasound, which makes them difficult to aggregate. They do not collectively form an adequate basis for deciding whether to recommend early or late ultrasound pregnancy screening on a routine basis.     

Ultrasonography in the diagnosis and management of abnormal early pregnancy

The demand for ultrasound in early pregnancy has been increasing steadily, and is now a routine investigation for most women within the first trimester of their pregnancy. It is a safe investigation which provides reassurance, charts normal development, and identifies women with abnormal or high risk pregnancies. Transvaginal ultrasound has revolutionized the diagnosis of early pregnancy as it can detect a pregnancy at an earlier stage, whether it is normal and therefore reassuring, or abnormal and require intervention. Ultrasound is also a useful tool to aid decisions regarding management of abnormal pregnancy, such as ectopic pregnancy or miscarriage. This chapter looks at the important role ultrasound plays in the diagnosis and management of abnormal pregnancy.     

Obstetrical ultrasonography

BACKGROUND: As with all new diagnostic options in medicine, great hope was placed in the introduction of high-resolution prenatal sonography. Progress tends to induce higher expectations. Patients and doctors alike may initially overestimate the possibilities of medical advances. QUESTION: The question at hand is whether we can validate a positive influence of prenatal ultrasound on the fetal and/or maternal pregnancy outcome, and how a sonographic routine screening should be structured. MATERIAL AND METHODS: This is an attempt to survey the heterogeneous pool of internationally published data with regard to these critical questions. RESULTS AND CONCLUSION: Different studies lead to a positive conclusion on the benefits of ultrasound monitoring in pregnant women. Ultrasound screening has a positive effect on medical as well as economic issues. Nevertheless litigation concerning prenatal diagnosis remains a growing problem.     

An evaluation of routine early pregnancy ultrasonography

A review of 1 000 pregnancies in which routine early pregnancy scanning was performed is reported. Ultrasound predicted accurately (to within +/- 14 days) the date of confinement in more than 90% of women who were unsure of their dates. Clinical estimation of gestation age compared well with ultrasound report in 90% of singleton pregnancies. Scanning diagnosed 3 out of 4 lethal congenital abnormalities in early pregnancy. The diagnosis of multiple pregnancy and placenta praevia have no immediate clinical implication in early pregnancy. Early pregnancy scan is recommended for women who are uncertain of their last menstrual period and for those with identified early pregnancy risks. Routine use of ultrasonography in early pregnancy should be related to the identified need of the population served and should be employed with caution. Where the policy of routine scanning is adopted, optional information is obtained when the procedure is carried out between the 14th and 18th week of gestation. Clinical pelvic examination in early pregnancy remains a valuable practice for the estimation of gestational age.     

Ultrasound in obstetrics and gynaecology

Ultrasound (US) is a key investigation in Obstetrics and Gynaecology and is commonly used in screening, diagnosing, treatment and follow-up. It is quick, cheap, widely available, portable and does not involve ionizing radiation. US can also be used to guide aspiration cytology or biopsy, as well as being a screening tool. This review discusses the role of ultrasound in both benign and malignant gynaecology, early pregnancy and obstetrics. The ultrasound findings of common female pelvic and obstetric pathology are considered and related to current evidence-based practice.     

Routine ultrasound screening in the third trimester: a population-based study

BACKGROUND: No population-based study has evaluated the effects of third trimester ultrasound screening on prognosis. OBJECTIVE: To study the effects of routine ultrasound screening in the third trimester on perinatal/infant mortality, prevalence of small for gestational age infants (SGA) and low Apgar score. STUDY DESIGN: Two university clinics using routine ultrasound screening in the third trimester were compared with seven county or district hospitals with no routine screening. Deliveries between 1985 and 1996 were included. In all, 16 municipalities including 56 371 pregnancies with routine screening were compared with 59 municipalities and 153 355 pregnancies without third trimester screening. An observational design was applied, using data stored during pregnancy, delivery, and during the first year (infant mortality) at the Swedish Medical Birth Registry, The National Board of Health and Welfare. Odds ratio with 95% confidence interval was used in the evaluation. End-points included incidence of SGA, perinatal/infant mortality, Apgar score at 5 min, cesarean section and instrumental delivery in areas with versus without routine third trimester screening. RESULTS: No significant difference was seen in the prevalence of the most extreme SGA (< -3 SD from the mean), perinatal complications including cesarean section or instrumental delivery, or perinatal/infant mortality between units with versus without routine ultrasound screening in the third trimester. CONCLUSION: Added to the findings of previous small randomized studies, it seems as if routine third trimester ultrasound screening in an unselected population does not reduce perinatal mortality or early neonatal morbidity, expressed as Apgar scores or SGA.     

Should second trimester ultrasound be routine for all pregnancies?

Ultrasound use has become ubiquitous in pregnancy. We review the evidence regarding the benefits of routine ultrasound use during pregnancy. Routine ultrasound use before 24 weeks improves detection of undiagnosed twins, reduces postdates inductions, and allows detection of fetal anomalies before birth. Wide variations exist in the sensitivity of ultrasound in detecting fetal anomalies. These may be related to equipment, training, and maternal characteristics, such as obesity. Standards have been developed for the performance of routine fetal ultrasonography in the second trimester. The benefits of routine first trimester ultrasound in the diagnosis of structural fetal anomalies or of routine ultrasonography after 24 weeks are not proven. As ultrasound technology improves and obstetrical care changes, new uses of routine ultrasonography may emerge.     

Ultrasound During Pregnancy: A Discussion

PREAMBLE: Prenatal screening by ultrasound is increasing in the United States. In 1990, 52 percent of mothers who had live births received ultrasound, compared with 48 percent in 1989 (Monthly Vital Stat Rep 1993;42:2(S):6). A recent multicenter, randomized study of 15,151 low-risk pregnant women, conducted by the Routine Antenatal Diagnostic Imaging With Ultrasound (RADIUS) Study Group, reported no significant differences in pregnancy outcomes between women who received no ultrasound scan and women who received two scans during pregnancy (N Engl J Med 1993;329:821–827). Ewigman et al concluded, “The adoption of routine ultrasound screening in the United States would add considerably to the cost of care in pregnancy, with no improvement in perinatal outcome.” This interview and discussion took place at the Tenth Birth Conference, October 31-November 1, 1992, in Boston. It was conducted by Max Allen, producer, Canadian Broadcasting Corporation, and broadcast as part of a radio program, “Birth and Technology,” on CBC Ideas, February 15, 1993.     

Does fetal screening affect women's worries about the health of their baby? A randomized controlled trial of ultrasound screening for Down's syndrome versus routine ultrasound screening

BACKGROUND: Screening for fetal abnormality may increase women's anxiety as attention is directed at the possibility of something being wrong with the baby. The aim of this study was to evaluate the effect of ultrasound screening for Down's syndrome on women's anxiety in mid-pregnancy and 2 months after delivery. METHOD: Two thousand and twenty-six women were randomly allocated to an ultrasound examination at 12-14 gestational weeks (gws) including risk assessment for Down's syndrome or to a routine scan at 15-20 gws. Questionnaires including the State-Trait Anxiety Inventory (STAI), the Cambridge Worry Scale (CWS), and the Edinburgh Postnatal Depression Scale (EPDS) were filled in at baseline in early pregnancy, at 24 gws and 2 months after delivery. RESULTS: No statistically significant differences were found between the trial groups regarding women's worries about the health of the baby, general anxiety and depressive symptoms during pregnancy or 2 months after delivery. Women's worries about something being wrong with the baby in the early ultrasound group and routine group, respectively, decreased from baseline (39.1% versus 36.0%) to mid-pregnancy (29.2% versus 27.8%), and finally to 2 months after delivery (5.2% versus 6.6%). CONCLUSION: Fetal screening for Down's syndrome by an early ultrasound scan did not cause more anxiety or concerns about the health of the baby in mid-pregnancy or 2 months after birth than in women who had a routine scan.     

The use of first trimester ultrasound in routine practice.

Since the introduction of ultrasound scanning in early pregnancy, transabdominal or transvaginal ultrasonography has taken on an important role in routine clinical practice in terms of the care of the fetus and the mother. The use of ultrasound in very early pregnancy makes it possible to confirm the intrauterine living embryo or diagnose the extrauterine pregnancy in which medical treatment with low morbidity is feasible with early detection. Early scanning can provide exact dating with acceptable error, which is one of problems encountered in clinical practice. Chorionicity can be correctly established by early scanning (before 14 weeks of gestation) to manage multiple pregnancies properly. The nuchal translucency, which is a transitory abnormality, can be measured for the early screening of Down's syndrome, trisomy-18, trisomy-13, Turner's and some other aneuploidy at the 11-14 weeks gestation with approximately 80% detection rate. Early diagnosis of some major abnormalities such as anencephaly, megacystis, polycystic kidney, omphalocele is also possible by early scanning. This provides great advantages as the clinical management will be quite different for a case of omphalocele or megacystis. Therefore the early ultrasound scanning has become a routine standard method in the care of the pregnant woman.     

Long-term experience of general ultrasound screening in pregnancy

Since January 1, 1974, 43,000 routine ultrasound examinations have been performed on 22,400 pregnant women in the Department of Obstetrics and Gynecology, MalmöGeneral Hospital. At the present time, one examination is performed in the seventeenth week of pregnancy and one in thirty-third week. At the first examination, the number of fetuses, fetal anatomy, cardiac activity, and placental site are indicated. Fetometry is performed. Gestational age is adjusted according to the value of the biparietal diameter. The second ultrasound examination is aimed at detecting fetal growth deviations and malformations. In 15% of all pregnancies, ultrasound corrected gestational age by more than 14 days. Ultrasound appeared to be superior to the clinical assessment in 88% of these discrepant pregnancies in predicting date of delivery. The early examination detected 98% of the twin pregnancies, with no false positive results. If an ultrasound examination had been performed within 3 weeks of delivery, 92% of the fetuses with growth retardation were detected. Altogether, the program detected 60% of the growth-retarded fetuses. In 0.4% of the examinations, malformations were detected (0.6% during the last 2 years). A cost-benefit analysis suggested that large economical gains are to be realized by screening. However, organizational and educational problems must be properly solved before general screening is offered to a healthy pregnant population.     

Role of ultrasound in obstetrics

Ultrasound has largely been believed to be useful in pregnancy, providing carers with ever-increasing information. The application of ultrasound in obstetrics may be broadly classified as either elective or reactive. Elective or planned use implies scanning to detect potential problems in an otherwise seemingly uncomplicated pregnancy (screening), whereas reactive use is the application of ultrasound to help in the management of a clinical problem (e.g. suspected intrauterine growth restriction). Information from ultrasound examinations is not necessarily helpful. Ultrasound is an aid to diagnosis, whereas excessive reliance on this tool to the neglect of the clinical situation is likely to do more harm than good. Advances in technology have made it possible to image the fetus in great detail. Our understanding and knowledge must keep pace with technology, to ensure that we correctly use and interpret ultrasound.     

Type III congenital cystic adenomatoid malformation associated with elevated maternal serum alpha-fetoprotein

Congenital cystic adenomatoid malformation Type III with fetal ascites was diagnosed in a 19-week fetus after finding an abnormally elevated maternal serum alpha-fetoprotein value during routine screening. This discovery led to early elective termination of pregnancy. Sonographic evaluation of the fetal thorax is recommended in all cases referred for ultrasound because of unexplained elevation of maternal serum alpha-fetoprotein.     

Ultrasound prenatal diagnosis of structural abnormalities

One of the major roles of ultrasound in pregnancy is the detection of structural abnormalities. Ultrasound screening has become an accepted part of antenatal practice. However there is a wide variety in the practice between different centers. The majority of fetal anomalies are diagnosed by ultrasound in the second trimester. However, a number of abnormalities are amenable to diagnosis as early as 11–14 weeks gestation. National guidelines have been adopted in an attempt to standardize the practice in the UK. Prenatal detection rate is higher in countries with a national screening program. Prenatal ultrasound is a screening test and will have false negatives and positives.Structural abnormalities can occur as isolated events, as part of a genetic syndrome or as a result of a chromosomal abnormality. When an abnormality is detected prenatally, a multidisciplinary approach is necessary to optimize the outcome. It is important to provide appropriate information to the prospective parents but remain non-judgmental with their decision.     

Poor pregnancy outcome in women with type 1 diabetes is predicted by elevated HbA1c and spikes of high glucose values in the third trimester

Abstract

Objective: To analyse data from a randomised, controlled study of prandial insulin aspart versus human insulin, both with NPH insulin, in pregnant women with type 1 diabetes for potential factors predicting poor pregnancy outcomes.

Research design/method: Post hoc analysis including 91 subjects randomised prior to pregnancy with known outcome in early pregnancy and 259 subjects randomised prior to pregnancy/during pregnancy of <10 weeks’ gestation with known late-pregnancy outcomes. Poor early-pregnancy outcomes included fetal loss <22 gestational weeks and/or congenital malformation (n?=?18). Poor late-pregnancy outcomes included: composite endpoint including pre-eclampsia, preterm delivery and perinatal death (n?=?78); preterm delivery (n?=?63); and excessive fetal growth (n?=?88).

Results: 18 patients experienced a malformed/lost fetus in early pregnancy – none preceded by severe hypoglycaemia. Albuminuria in early pregnancy was a significant predictor of poor late-pregnancy outcome (composite endpoint; p?=?0.012). In the third trimester, elevated HbA_1c,?≥?1 plasma glucose (PG) measurement >11?mmol/L (198?mg/dL) and %PG values outside 3.9–7.0?mmol/L (70–126?mg/dL) were significant predictors of poor late-pregnancy outcomes (all p?<?0.05).

Conclusions: Elevated HbA_1c, high glucose spikes and out-of-range %PG in the third trimester, and albuminuria in early pregnancy, are associated with poor late-pregnancy outcomes.     

Ultrasound in prenatal diagnosis: polemics around routine ultrasound screening for second trimester fetal malformations

Ultrasound for routine fetal malformation screening has been polemical from its early beginning because of the very broad range of diagnosis rates disclosed, i.e. from 13% to 82%, average 27.5%. A review of available studies is proposed to assess objectively the efficacy of ultrasound, considering also economical, ethical and methodological aspects as influential factors for choosing a routine screening policy. The utility of fetal malformation diagnosis before birth is brought forward, including second opinion, karyotyping, poly-disciplinary case discussion prior to management. Method and material of reviewed studies considerably vary and might influence the sensitivity results, as the choice of the population sample and selection of pregnant women, gestation age at screening, distribution of malformation among systems or tracts, exclusion of some fetal malformation and the routine practice of autopsy. Efficiency of screening studies is compared, and among them Radius and Eurofetus studies. Average sensitivity is finally considered as satisfactory in the daily practice when operated by trained personnel. The importance of additional factors for successful screening are emphasized such as education, equipment quality and fetal ultrasound examination at different gestation age for a better understanding of natural history of fetal morphology.     

Ultrasound screening of fetal structural abnormalities at 12 to 14 weeks in Hong Kong

OBJECTIVE: Ultrasound screening for fetal abnormalities is conventionally performed at 18 to 20 weeks of gestation. Recent data suggested that many fetal structural abnormalities could be detected by ultrasound examination at 12 to 14 weeks of pregnancy. In this study, we investigated the effectiveness of early ultrasound examination in the detection of fetal abnormalities in women aged 35 years or older. METHODS: From February 1998 to March 2001, pregnant women aged 35 or above were examined by transabdominal and transvaginal sonography between 12 and 14 weeks of gestation. If the anatomical survey was normal, the women underwent routine 16- to 20-week ultrasound examination. Pregnancy outcome was obtained from the hospital records or by contacting the subjects. RESULTS: Twenty-six of the 1609 fetuses had structural abnormalities. Fourteen were detected at the ultrasound examination at 12 to 14 weeks. Detection rate was 53.8% (14/26; 95% CI 44, 64) with a false-positive rate of 0.3% (5/1583; 95% CI 0.16, 0.44). Six additional abnormalities (23.1%, 6/26) were detected at 16- to 20-week ultrasound examination. The overall detection rate of structural abnormalities was 76.9% (20/26; 95% CI 68.6, 85.2). CONCLUSIONS: The effectiveness of ultrasound examination at 12 to 14 weeks to screen for fetal abnormalities approached that achieved at 20 weeks and can be a good adjunct to the conventional examination.