Ultrasound screening and perinatal mortality: controlled trial of systematic one-stage screening in pregnancy. The Helsinki Ultrasound Trial

Guidelines for the management of pregnancy at 41+0 to 42+0 weeks

OBJECTIVE

To provide evidence-based guidelines for the management of pregnancy at 41+0 to 42+0 weeks.

OUTCOMES

Reduction of perinatal mortality associated with Caesarean section at 41+0 to 42+0 weeks of pregnancy.

EVIDENCE

The Medline database, the Cochrane Library, and the American College of Obstetricians and Gynecologists and the Royal College of Obstetricians and Gynecologists, were searched for English language articles published between 1966 and March 2007, using the following key words: prolonged pregnancy, post-term pregnancy, and postdates pregnancy. The quality of evidence was evaluated and recommendations were made according to guidelines developed by the Canadian Task Force on Preventive Health Care. Recommendations 1. First trimester ultrasound should be offered, ideally between 11 and 14 weeks, to all women, as it is a more accurate assessment of gestational age than last menstrual period with fewer pregnancies prolonged past 41+0 weeks. (I-A) 2. If there is a difference of greater than 5 days between gestational age dated using the last menstrual period and first trimester ultrasound, the estimated date of delivery should be adjusted as per the first trimester ultrasound. (I-A) 3. If there is a difference of greater than 10 days between gestational age dated using the last menstrual period and second trimester ultrasound, the estimated date of delivery should be adjusted as per the second trimester ultrasound. (I-A) 4. When there has been both a first and second trimester ultrasound, gestational age should be determined by the earliest ultrasound. (I-A) 5. Women should be offered the option of membrane sweeping commencing at 38 to 41 weeks, following a discussion of risks and benefits. (I-A) 6. Women should be offered induction at 41+0 to 42+0 weeks, as the present evidence reveals a decrease in perinatal mortality without increased risk of Caesarean section. (I-A) 7. Antenatal testing used in the monitoring of the 41- to 42-week pregnancy should include at least a non-stress test and an assessment of amniotic fluid volume. (I-A) 8. Each obstetrical department should establish guidelines dependent on local resources for scheduling of labour induction. (I-A).

Prenatal imaging: ultrasonography and magnetic resonance imaging

The Eunice Kennedy Shriver National Institute of Child Health and Human Development held a workshop on September 18-19, 2006, to summarize the available evidence on the role and performance of current fetal imaging technology and to establish a research agenda. Ultrasonography is the imaging modality of choice for pregnancy evaluation due to its relatively low cost, real-time capability, safety, and operator comfort and experience. First-trimester ultrasonography extends the available window for fetal observation and raises the possibility of performing an early anatomic survey. Three-dimensional ultrasonography has the potential to expand the clinical application of ultrasonography by permitting local acquisition of volumes and remote review and interpretation at specialized centers. New advances allow performance of fetal magnetic resonance imaging (MRI) without maternal or fetal sedation, with improved characterization and prediction of prognosis of certain fetal central nervous system anomalies such as ventriculomegaly when compared with ultrasonography. Fewer data exist on the usefulness of fetal MRI for non-central nervous system anomalies.

Fetal ultrasound: mechanical effects

In this discussion, any biological effect of ultrasound that is accompanied by temperature increments less than 1 degrees C above normal physiologic levels is called a mechanical effect. However, one should keep in mind that the term mechanical effect also includes processes that are not of a mechanical nature but arise secondary to mechanical interaction between ultrasound and tissues, such as chemical reactions initiated by free oxygen species generated during cavitation and sonoluminescence. Investigations with laboratory animals have documented that pulsed ultrasound can produce damage to biological tissues in vivo through nonthermal mechanisms. The acoustic output used to induce these adverse bio-effects is considerably greater than the output of diagnostic devices when gas bodies are not present. However, low-intensity pulsed ultrasound is used clinically to accelerate the bone fracture repair process and induce healing of nonunions in humans. Low-intensity pulsed ultrasound also has been shown to enhance repair of soft tissue damage and accelerate nerve regeneration in animal models. Although such exposures to low intensity do not appear to cause damage to exposed tissues, they do raise questions about the acoustic threshold that might induce potentially adverse developmental effects in the fetus. To date, bioeffects studies in humans do not substantiate a causal relationship between diagnostic ultrasound exposure during pregnancy and adverse biological effects to the fetus. However, the epidemiologic studies were conducted with commercially available devices predating 1992, having outputs not exceeding a derated spatial-peak temporal-average intensity (ISPTA.3) of 94 mW/cm2. Current limits in the United States allow an ISPTA.3 of 720 mW/cm2 for obstetric modes. At the time of this report, available evidence, experimental or epidemiologic, is insufficient to conclude that there is a causal relationship between obstetric diagnostic ultrasound exposure and adverse nonthermal effects to the fetus. However, low-intensity pulsed ultrasound effects reported in humans and animal models indicate a need for further investigation of potentially adverse developmental effects.

Information, knowledge and expectations of the routine ultrasound scan

OBJECTIVE

To examine the current provision of pre-ultrasound information to women; to determine if the information provided was related to women's knowledge of the routine second trimester ultrasound; and to describe women's expectations of the scan.

DESIGN

A descriptive survey, before and after design.

SETTING

Tertiary referral centre in the Republic of Ireland.

PARTICIPANTS

A convenience sample of pregnant women attending for routine second trimester ultrasound scan.

MEASUREMENTS

Self-report questionnaires were used to explore the availability of information about the test, the extent of women's knowledge and expectations of the examination, and the degree to which expectations were achieved.

FINDINGS

Most women received little information from health professionals about the capability and limitations of the scan, and had expectations that exceeded the purpose and ability of the examination. Most women, however, stated that their expectations were met in most cases. Although the routine ultrasound in the study site is not a targeted fetal anatomical survey, most women were concerned with this aspect of the test.

KEY CONCLUSIONS

If women are to have realistic expectations of the routine ultrasound scan, then improvements are required in the provision of pre-ultrasound information, particularly in relation to the technological limitations of the examination. Consideration should be given to the context of the high appeal associated with visualising the fetus for women when unachievable expectations are reported as having been met.

IMPLICATIONS FOR PRACTICE

Any development of prenatal screening programmes that will uncover fetal abnormalities needs to be considered in context, in particular when termination of pregnancy is not available within the jurisdiction. Women had expectations of the examination that could not, because of technological limitations, have been met by the examination, but which they perceived to have been met. Knowledge of the purpose, capabilities and limitations of the routine second trimester ultrasound scan was not influenced by the mode of information provision.

Epidemiological prenatal ultrasound studies

Epidemiological studies have indicated no association between diagnostic ultrasound exposure during pregnancy and childhood malignancies. Diagnostic ultrasound imaging does not seem to influence birth weight, whereas frequent Doppler ultrasound was associated with reduced birth weight in one study. Most experts do not believe that ultrasound exposure during pregnancy is associated with reduced birth weight. There are no confirmed statistically significant associations between ultrasound and dyslexia and neurological development during childhood. However, two randomised controlled trials and two cohort studies have been unable to rule out a possible association between ultrasound and left-handedness among males.

Correlation between prenatal ultrasound and autopsy findings: A study of second-trimester abortions

OBJECTIVE

To evaluate discrepancies between sonographic and autopsy findings following termination of pregnancy (TOP) in the second trimester.

METHODS

This retrospective report is based on 288 consecutive second-trimester abortions carried out because of fetal malformations diagnosed by ultrasound examination at a tertiary referral center. The correlation between the results from the ultrasound and autopsy examinations was evaluated.

RESULTS

Autopsy was performed in 274 cases. In 160 of the 274 pregnancies (58.4%) there was full agreement between the two examination methods. Findings detected by autopsy (in addition to those leading to termination) were not observed by ultrasonography in 86 (31.4%) of the pregnancies; of the 64 malformations that occurred, 30 (46.9%) were judged as 'detectable'. In 27 (9.9%) pregnancies, observations made by ultrasound (in addition to those leading to termination) were not confirmed at autopsy. In one pregnancy, postmortem radiology examination-but not autopsy-confirmed the ultrasound observations. No pregnancies were terminated because of false positive ultrasound observations. The correlation between ultrasound and autopsy findings was evaluated by three investigators; the inter-rater agreement was high (kappa = 0.85).

CONCLUSION

Discrepancies between ultrasound and autopsy findings were observed in about 40% of the pregnancies. These discrepancies confirm the need for autopsy following TOP.

Prediction of delivery date by sonography in the first and second trimesters

OBJECTIVE

To compare the dates of delivery predicted by last menstrual period (LMP), crown-rump length (CRL) and biparietal diameter (BPD) with the actual date of delivery in a population of pregnant women divided into those with certain and those with uncertain LMP.

METHODS

Healthy women were enrolled at the first visit during their pregnancy to a general practitioner in Odense, Denmark, and underwent ultrasound examinations in the first and second trimesters. Data from a study of 798 women who gave birth in the period August 2001 to April 2003 are presented, although only the 657 spontaneous deliveries were used for analysis (n = 339 and 318 in the certain and uncertain LMP groups, respectively). Data on pregnancy and delivery were collected from the medical records. Wilcoxon's signed rank test was used to test the hypothesis of no difference in prediction error (predicted - actual date of delivery) between the three methods.

RESULTS

The median prediction errors estimated by sonography in the first and second trimesters and by corrected LMP according to cycle length were 2.32, 0.16, and 3.00 days, respectively, in women with certain LMP, and 1.71, 0.00, and 3.00 days, respectively, in women with uncertain LMP. The median gestational age at delivery estimated by sonography in the first and second trimesters and by corrected LMP according to cycle length was 282, 280, and 283 days, respectively, in both groups.

CONCLUSION

An ultrasound examination in the second trimester (17-22 completed weeks) is the best predictor of the date of delivery at the individual level, followed by an ultrasound examination in the first trimester. Having an uncertain LMP does not affect the sonographic prediction of date of delivery.

Rapporteur report: Epidemiology

Three talks were presented in the session on "Epidemiology". The first talk was a review of prenatal studies. The second talk presented epidemiological evidence from prenatal studies. The third talk presented general issues regarding the planning of an epidemiological study. It was noted that epidemiological studies of prenatal exposures use data from the early 1980s when ultrasound was first introduced for foetal scans. These studies did not show associations between prenatal ultrasound scanning and childhood cancer, reduced birth weight, impaired childhood growth or neurological development in childhood. However, there was a possible association between prenatal ultrasound scanning and left-handedness in boys. The aetiology of this association remains uncertain.

The examiner's ultrasound experience has a significant impact on the detection rate of congenital heart defects at the second-trimester fetal examination

OBJECTIVES

To determine whether training and experience in performing ultrasound examinations are factors that influence the prenatal detection of congenital heart defects (CHDs) in a non-selected population, in order to evaluate and improve the current training program.

METHODS

All pregnant women who received a routine second-trimester ultrasound scan by a sonographer/midwife and delivered at our hospital between February 1991 and December 2001 were registered prospectively. Less experienced sonographer/midwives who had performed between 200 and 2000 routine examinations were compared with experienced sonographer/midwives who had carried out more than 2000 examinations. During the first 5 years of the study the heart structures obtained were registered in detail.

RESULTS

Of 29,035 fetuses, 35/82 (43%) major CHDs were prenatally detected at the routine examination. The experienced sonographer/midwives obtained both the four-chamber view and the great arteries in 75%; the figure for the less experienced sonographer/midwives was 36% (P < 0.001). The differences in detecting major heart defects were 22/42 (52%) and 13/40 (32.5%), isolated CHDs 8/18 (44%) and 6/22 (27%) and CHDs with associated malformations 14/24 (58%) and 7/18 (39%), respectively. In both groups some CHDs with an abnormal four-chamber view were missed, although the experienced sonographer/midwives recognized significantly more of the abnormal views than did the less experienced sonographer/midwives (P = 0.002).

CONCLUSIONS

Experience has a significant impact on the examination of the fetal heart and the prenatal detection rate of major CHDs. To avoid a relatively long learning curve, ultrasound education needs to intensify the teaching of the basic four-chamber view. The great arteries should be included after additional training. Those basic views of the fetal heart must be mastered before new views and advanced technology are added to the fetal heart examination.

Does a first trimester dating scan using crown rump length measurement reduce the rate of induction of labour for prolonged pregnancy? An uncompleted randomised controlled trial of 463 women

OBJECTIVE

To evaluate the effect of a first trimester ultrasound dating scan on the rate of induction of labour for prolonged pregnancy.

DESIGN

Randomised controlled trial to include 400 women in each arm of the trial.

SETTING

Participating general practices and a district general teaching hospital.

POPULATION

Women attending their general practitioner in the first trimester to confirm pregnancy, in whom a first trimester ultrasound scan was not indicated.

METHODS

Women randomised to the study group (scan group) underwent an ultrasound dating scan between 8 and 12 weeks, measuring crown-rump length. The estimated date of delivery (EDD) was changed if there was a discrepancy of more than 5 days from the gestation, calculated from the last menstrual period (LMP). For the remaining women (no-scan group), gestation was determined using the LMP.

MAIN OUTCOME MEASURES

The rate of induction of labour for prolonged pregnancy.

RESULTS

Due to circumstances beyond the researchers' control, recruitment was abandoned when 463 women had been enrolled. The EDD was adjusted in 13 (5.7%) women in the scan group and in 2 (0.9%) in the no-scan group. There was no difference in the rate of induction for prolonged pregnancy between the scan (19 [8.2%]) and the no-scan (17 [7.4%]) groups (relative risk 1.10; 95% CI 0.59-2.07).

CONCLUSIONS

Acknowledging the reduced numbers recruited for study, it is concluded that there is no evidence that a first trimester ultrasound dating scan reduces the rate of induction of labour for prolonged pregnancy and may result in a more expensive healthcare strategy.

False positives in the prenatal ultrasound screening of fetal structural anomalies

OBJECTIVE

To describe the false-positive diagnoses of prenatal ultrasound screening of fetal structural anomalies.

METHODS

Pregnancies with fetal structural anomalies either detected prenatally in our center or referred to us, were registered, evaluated, and followed-up prospectively by a multidisciplinary Congenital Defects Committee. After postnatal follow-up was completed, cases were assigned as true positives, false positives or false negatives and categorized by anatomical systems. Pregnancies referred with a nonconfirmed suspicion of anomaly were not included. The false-positive diagnoses were analyzed.

RESULTS

From 1994 to 2004, 903 new registry entries of fetuses structurally abnormal at ultrasound with a complete follow-up were included in the Committee database. There were 76 false positives, accounting for 9.3% of all the prenatally established diagnoses. The urinary tract anomalies were the most frequent false-positive diagnoses found (n = 25; accounting for 8.7% of the urinary tract defects), but the genital anomalies showed the higher rate of no confirmation (n = 5; 15.2%). The specific anomalies most commonly not confirmed were renal pyelectasis (n = 9), cerebral ventriculomegaly (n = 9), abdominal cysts (n = 7) and short limbs (n = 7).

CONCLUSION

Several prenatally diagnosed anomalies would benefit from prudent counseling, because they may be normal variants or transient findings.

Routine ultrasound screening and detection of congenital anomalies outside a university setting

BACKGROUND

To assess the sensitivity for detecting fetal congenital anomalies by a routine ultrasound examination program at midtrimester performed in an unselected population by midwives and specialists in obstetrics and gynecology.

METHODS

Six hundred seventy-six of the pregnancies had the midtrimester ultrasound examinations performed outside the county. Three hundred seventeen of the women had midtrimester ultrasound examinations performed in the county, but delivered outside the county. A total of 18 181 pregnancies were eligible for the study.

RESULTS

Altogether there were 267 fetuses and newborns with anomalies, which gives a prevalence of 1.5%. One hundred three of the 267 anomalies were detected at the midtrimester ultrasound examination, yielding a sensitivity of 39.0%. There were 11 false positives and 163 remained undiagnosed (false negatives), which gives a specificity of 99.9% and a positive predictive value of 90.4%. The sensitivity for detecting anomalies ranged from 74.4 to 8.3% according to the organ system of the fetus.

CONCLUSIONS

Our study shows that midtrimester routine ultrasound examination in district hospitals can achieve a detection rate of congenital anomalies comparable with tertiary centers. One-stage ultrasound examination at midtrimester gives acceptable results concerning congenital anomalies with few false-positive results.

Is an excessive number of prenatal echographies a risk for fetal growth?

AIM

To assess whether a very high number of prenatal ultrasonographies affects birthweight.

POPULATION AND METHODS

We studied 1203 consecutive women who delivered in Siena Hospital. Exclusion criteria were the following: twin pregnancy, maternal smoke or alcohol ingestion in pregnancy, gestational diabetes, placenta or umbilical cord defects, gestational age at birth <37 weeks, and major malformations. We analysed birthweights in relation to the number of ultrasound examinations. 120 women had undergone a minimum number (three or less-base group) and 167 a maximum number (nine or more-intensive group) of fetal US scans. We compared the birthweight of the children born in these two groups and the correlation between number of US scans and birthweight in the whole population.

RESULTS

Mean birthweights of the base and the intensive groups were 3389.5+/-434 g and 3268+/-438 g, respectively (p=0.0206). Nevertheless, the regression study did not show a significant correlation between birthweight and number of US scans. The mean age of the base group was 30.1+/-5.3 years and that of the intensive group was 32.09+/-4.99 years (p=0.0018). Eighteen women of base group underwent amniocenteses vs. 71 in the intensive group (p<0.001). In the base group 57.5% of the mothers had low school level vs. 24.4% in the intensive group (p<0.01).

CONCLUSION

More studies are needed to confirm or exclude any relationship between an intensive use of prenatal ultrasounds and birthweight, and to exclude other effects of ultrasounds on children's health. Moreover, our study shows an excess of prenatal diagnostic procedures, the causes of which should be investigated.

Fetal Soft Markers in Obstetric Ultrasound

This document has been archived because it contains outdated information. It should not be consulted for clinical use, but for historical research only. Please visit the journal website for the most recent guidelines.

Prenatal diagnosis of severe structural congenital malformations in Europe

OBJECTIVES

To assess at a population-based level the frequency with which severe structural congenital malformations are detected prenatally in Europe and the gestational age at detection, and to describe regional variation in these indicators.

METHODS

In the period 1995-1999, data were obtained from 17 European population-based registries of congenital malformations (EUROCAT). Included were all live births, fetal deaths and terminations of pregnancy diagnosed with one or more of the following malformations: anencephalus, encephalocele, spina bifida, hydrocephalus, transposition of great arteries, hypoplastic left heart, limb reduction defect, bilateral renal agenesis, diaphragmatic hernia, omphalocele and gastroschisis.

RESULTS

The 17 registries reported 4366 cases diagnosed with the 11 severe structural malformations and of these 2300 were live births (53%), 181 were fetal deaths (4%) and 1863 were terminations of pregnancy (43%); in 22 cases pregnancy outcome was unknown. The overall prenatal detection rate was 64% (range, 25-88% across regions). The proportion of terminations of pregnancy varied between regions from 15% to 59% of all cases. Gestational age at discovery for prenatally diagnosed cases was less than 24 weeks for 68% (range, 36-88%) of cases. There was a significant relationship between high prenatal detection rate and early diagnosis (P < 0.0001). For individual malformations, the prenatal detection rate was highest for anencephalus (469/498, 94%) and lowest for transposition of the great arteries (89/324, 27%). Termination of pregnancy was performed in more than half of the prenatally diagnosed cases, except for those with transposition of the great arteries, diaphragmatic hernia and gastroschisis, in which 30-40% of the pregnancies with a prenatal diagnosis were terminated.

CONCLUSION

European countries currently vary widely in the provision and uptake of prenatal screening and its quality, as well as the "culture" in terms of decision to continue the pregnancy. This inevitably contributes to variation between countries in perinatal and infant mortality and in childhood prevalence and cost to health services of congenital anomalies.

Correlation between self-reported gestational age and ultrasound measurements

BACKGROUND

We studied the agreement between different measurements of gestational age, i.e. self-reported gestational age in the Danish National Birth Cohort Study, ultrasound-estimated gestational age from the medical records in one Danish county and gestational age from the Danish National Hospital Discharge Register.

METHODS

The ultrasound-estimated gestational length was based on the size of the biparietal diameter. The ultrasound-estimated gestational length was related to corrected and uncorrected last menstrual period estimates in the Danish National Cohort Study, and to the gestational length recorded in the Danish National Discharge Register. Non-parametric statistics were used in the analysis.

RESULTS

The gestational ages estimated by ultrasound were 2-3 days shorter than gestational ages estimated by the other methods. The gestational ages recorded by the Discharge Register and the gestational ages based on corrected last menstrual period did not differ significantly.

CONCLUSION

The self-reported gestational age in The Danish National Birth Cohort is in good concordance both with data from the National Hospital Discharge Register and with ultrasound-estimated gestational age.

Two-stage ultrasonography in screening for fetal anomalies at 13-14 and 18-22 weeks of gestation

BACKGROUND

The aim of this study was to assess the value of two-stage screening by ultrasonography in detecting selected major fetal anomalies in a low-risk obstetric population.

METHODS

In a defined geographic area, 4789 consecutive low-risk pregnant women participated in screening by two-stage ultrasonography as part of routine maternal care. The examinations were usually performed by specially trained midwives at 13-14 and 18-22 weeks of gestation. Of the women, 4073 had both scans, 440 had the early one only, and 276 the late scan only. Pregnancy outcomes were ascertained from obstetric and pediatric records, and the data were supplemented with information from the national birth and malformation registries.

RESULTS

Of the 4855 fetuses, 33 (0.7%) had major structural defects considered detectable by ultrasonography. Of these, six (18%) were identified at the early scan, and an additional 10 (30%) at the late scan, yielding a total sensitivity of 48% for the two-stage screening. Twenty offspring had chromosomal abnormalities; 10 were identified by increased nuchal translucency at the early scan, one additional one (by hydronephrosis) at the late scan, and the remaining nine at birth.

CONCLUSIONS

In a low-risk population, first-trimester scanning is useful in finding fetuses with chromosomal anomalies, but a second-trimester scan is needed for other types of defects. The sensitivity of routine screening by midwives for fetal structural defects in a general obstetric population remains lower than that reported by specialized centers.

Ultrasound simulators: experience with the SonoTrainer and comparative review of other training systems

Ultrasound has become indispensable in prenatal diagnosis. Ultrasound training, however, still lacks proper quality assessment and control. Moreover, most fetal anomalies which must be diagnosed during pregnancy are extremely rare. Ultrasound simulators could provide an opportunity to overcome this dilemma. This review summarizes the potential benefits of simulator-based ultrasound training, briefly describes the properties of a variety of ultrasound simulators that have been developed for various applications including prenatal diagnosis, and presents the SonoTrainer sonography simulation system which makes it possible to run a real-time simulation of a complete prenatal ultrasound examination. We evaluated the system for the training of first- and second-trimester screening for both normal and pathological findings and found that physicians who received theoretical training and were additionally trained with the simulator (T + S) significantly improved their skills in measurements of nuchal translucency thickness (NT) and crown-rump length (CRL) as compared with colleagues who only underwent theoretical instruction (T) [mean +/- SD NT deviation: 0.31 +/- 0.1 mm (T + S) vs. 0.62 +/- 0.2 mm (T), P < 0.05; mean +/- SD CRL deviation: 1.48 +/- 2.0 mm (T + S) vs. 3.27 +/- 2.5 (T), P < 0.05]. Simulator-based training enabled physicians to diagnose rare fetal anomalies in the second trimester with a sensitivity of 86% and a specificity of 100%. In a study in which second-trimester scans including fetal anomalies were presented to physicians, 96% of the participants subjectively estimated their training effect as being good. We therefore conclude that simulator-based training would provide an ideal educational tool to test, improve and monitor a physician's or technician's ultrasound skills in detecting fetal anomalies.

The impact of multiple pregnancies and malformations on perinatal mortality

AIM

To evaluate the impact of the rate of multiple pregnancies and congenital malformations on perinatal mortality.

METHODS

The study is based on data from the perinatal audit in Vejle County Denmark. Fetal deaths with gestational age > or = 22 weeks and deaths in livebirths within the first 28 days after birth were included in the calculated perinatal mortality. Total number of births was 30,181 and 252 pregnancies and 268 fetuses/infants were evaluated. The study period was 1995-2000. There was no routine ultrasound screening for congenital malformations in the county, though midtrimester ultrasound was used to assess gestational age.

RESULTS

Perinatal mortality was 8.9 per 1000 births with no significant change over time. Rate of multiple pregnancies was 1.94% ranging from 1.81% during the first 3 years to 2.06% for the last 3 years (not significant). Fetuses and infants from multiple pregnancies contributed 18% of all deaths. Perinatal mortality for single births was 7.6 per 1000 births and for multiple births 42.2/1000 (P<0.0001). The distribution of gestational age for single and multiple births was highly significant (P<0.0001) with 67% of multiple pregnancies with GA < 28 weeks compared to 26% of single pregnancies. Nineteen percent of all deaths were caused by congenital malformations and the majority of these were potentially detectable by ultrasound investigation.

CONCLUSIONS

The increasing rate of multiple pregnancies makes it difficult to see improvements in perinatal mortality. Calculated from the perinatal mortality in single and multiple pregnancies in Vejle County assisted conceptions contribute with an an excess of 45 perinatal deaths per year in Denmark. The difference between countries in rate of multiple pregnancies and in prenatal ultrasound screening recommendations for malformations makes it difficult to compare perinatal mortality.

Cervical nitric oxide release in women postterm

OBJECTIVE

Nitric oxide may be a factor in cervical ripening. We compared the nitric oxide metabolite levels in cervical fluid in women going beyond term and in women delivering spontaneously at term.

METHODS

We studied a total of 208 women with singleton pregnancies: 108 women who went beyond term (294 days or longer), and 100 women who went spontaneously into labor at term. Cervical fluid samples, collected well before the initiation of labor, were assessed for nitric oxide metabolites using an assay with a detection limit of 3.8 micromol/L.

RESULTS

Women going beyond term had detectable levels of nitric oxide metabolites in their cervical fluid (60%) less often (P =.001) than women delivering at term (87%). The nitric oxide metabolite concentration in cervical fluid in women going beyond term (median 23.5 micromol/L; 95% confidence interval less than 3.8, 31.8) was 4.5 times lower (P <.001) than that in women delivering at term (median 106.0 micromol/L; 95% confidence interval 81.8, 135.0). Such a difference (14.0 versus 106.0 micromol/L) also existed when only the 66 women going into spontaneous postterm labor were included in the comparison. Both nulliparous (median less than 3.8 micromol/L) and parous (median 31.3 micromol/L) women going beyond term had lower (P <.01) cervical fluid nitric oxide metabolite levels than nulliparous and parous women delivering at term (medians 76.1 and 101.3 micromol/L, respectively). In the postterm group, women with cervical fluid nitric oxide metabolite concentrations at or below the median failed more often (P <.001) to progress in labor and had longer (P =.02) duration of labor than those with cervical fluid nitric oxide metabolite concentrations above the median.

CONCLUSION

Reduced cervical nitric oxide release may contribute to prolonged pregnancy.

LEVEL OF EVIDENCE

II-2

First trimester ultrasound screening is effective in reducing postterm labor induction rates: a randomized controlled trial

OBJECTIVE

This study was designed to test the null hypothesis that first trimester ultrasound crown-rump length measurement for gestational age determination will result in no difference in the rate of induction of labor for postterm pregnancy, compared with second trimester biometry alone.

STUDY DESIGN

Two hundred eighteen women were randomly assigned to receive either first trimester ultrasound screening or second trimester ultrasound screening to establish the expected date of confinement. Sample size was calculated by using a 2-tailed alpha=.05 and power (1-beta)=80%. Data were analyzed with chi(2) and Fisher exact tests.

RESULTS

Of 104 women randomly assigned to the first trimester screening group, 41.3% had their gestational age adjusted on the basis of the crown-rump length measurement. Of 92 women randomly assigned to the second trimester screening group, 10.9% were corrected as a result of biometry (P <.001, relative risk=0.26, 95% CI=0.15-0.46). Five women in the first trimester screening group and 12 women in the second trimester screening group had labor induced for postterm pregnancy (P=0.04, relative risk=0.37, 95% CI=0.14-0.96).

CONCLUSION

The application of a program of first trimester ultrasound screening to a low-risk obstetric population results in a significant reduction in the rate of labor induction for postterm pregnancy.

The evolving role of ultrasound in obstetrics/gynecology practice

The value of ultrasound examinations depends heavily on the preparation of the personnel carrying out the examination and the technical capabilities of the equipment they use. Only well-organized regional or national programs are able to provide high level, cost-effective care based on certification of quality. Such certification must include the training of professionals, the definition of competence levels, accreditation of laboratories and the establishment of professional protocols. Together, these factors can guarantee the standard of care and provide legal protection for practitioners. It is worth carrying out routine screening in each pregnancy because the majority of abnormalities occur in pregnancies with low risk. Abnormalities detected on screening cases and the examination of high risk groups should be referred to higher level centers. Here, appropriate technical background and qualified personnel are present to provide cost-effective care. At the same time, necessary invasive interventions can also be performed. A minimum of three screening tests should be performed during pregnancy. The first should be performed at the fetal age of 10-14 weeks to detect abnormalities and pathological conditions in early pregnancy. The second one has to be performed between the fetal ages of 18 and 22 weeks to assess detailed fetal anatomy and rate of development. The third should be performed between the fetal age of 30 and 34 weeks to assess fetal anatomy, rate of development, placentation and circulation. It is worth considering a fourth screening at approximately 36-38 weeks to assess the intrauterine condition of the fetus and determine the appropriate method of delivery. Finally, besides improving the standard of living, education, and hygienic conditions in developing countries, developed countries also have to help improve the standard of pregnancy care. Within this context, the dissemination of diagnostic ultrasound must be given special emphasis.

Routine fetal cardiac screening: what are we doing and what should we do?

In many countries, ultrasound examination is used in the second trimester to look for congenital malformations as part of routine prenatal care. While tertiary centres scanning high-risk pregnancies have reported a high degree of accuracy in the detection of congenital heart disease, many studies have shown that cardiac abnormalities are commonly overlooked during routine obstetric evaluation and there still remains a huge variation between centres. The majority of babies with congenital heart disease are born to mothers with no identifiable high-risk factors and so will not be detected unless there is widespread screening of the low-risk population. It is feasible to achieve widespread screening for fetal congenital heart disease in low-risk groups, but this does need commitment and effort from those performing the scans and those teaching them how to examine the heart. Staff performing routine obstetric ultrasound scans should learn a simple technique for examining the fetal heart and to use this in all patients. Links to a tertiary centre can provide support for checking scans of concern as well as for providing training and for obtaining feedback. In addition, an audit system needs to be established in each centre to trace false-positive and false-negative cases as well as to confirm true positives and true negatives.

A community-based obstetric ultrasound service

OBJECTIVES

To investigate the impact of an ultrasound dating service on obstetric services.

METHODS

A prospective trial with 3009 unselected women presenting for antenatal care at two Midwife Obstetric Units in a socioeconomically deprived urban area, South Africa. In the study unit, student ultrasonographers provided a basic ultrasound service. In the control unit, obstetric ultrasound was only available for specific indications. The main outcome measures were number of antenatal visits and referrals for fetal surveillance.

RESULTS

The two cohorts were comparable except for the number of primigravidas but stratified analysis according to parity did not affect the results. Ultrasonography did not alter pregnancy outcome but reduced the number of perceived preterm labors/ruptured membranes (12.0 vs. 16.7%, P<0.003), post-term deliveries (8.1 vs. 10.8%, P<0.04) and referrals for fetal surveillance [15.9 vs. 29.6%, P<0.000, RR 0.79 (0.71-0.88)].

CONCLUSIONS

This community-based basic ultrasound service significantly reduced referrals to a regional center for fetal surveillance and delivery.

Use of fetal magnetic resonance imaging in patients electing termination of pregnancy by dilation and evacuation

OBJECTIVE

The purpose of this study was to determine whether magnetic resonance imaging of the fetal brain before dilation and evacuation enhances diagnosis when equivocal ultrasound findings and disrupted autopsy specimens exist.

STUDY DESIGN

Patients with equivocal fetal brain abnormalities on ultrasound examination who were considering termination of pregnancy were evaluated retrospectively. Abdominal and pelvic magnetic resonance imaging was performed for further evaluation, and orthogonal fetal brain images were obtained. A multidisciplinary team reviewed all cases and discussed the findings, possible causes, and recurrence risks with each patient.

RESULTS

Seven patients with fetal brain anomalies underwent magnetic resonance imaging before dilation and evacuation. Magnetic resonance imaging diagnoses included intracranial hemorrhages, semilobar holoprosencephaly, intracranial teratoma, multiple cerebral infarcts, and unilateral cerebellar hypoplasia. In all cases, magnetic resonance imaging provided valuable information and helped distinguish possible genetic syndromes from likely sporadic disorders of brain development.

CONCLUSION

Magnetic resonance imaging can provide insight into diagnosis, cause, and recurrence risks for patients who choose dilation and evacuation because of fetal brain abnormalities.

Trends in elective terminations of pregnancy between 1989 and 2000 in a French county (the Isère)

OBJECTIVES

This study was performed in order to provide a description of indications for induced elective terminations of pregnancy (ETOP), their characteristics (e.g. gestational age), and their evolution over time.

DESIGN OF THE STUDY

This is an epidemiological study. The geographic area covered is the French county of 'Isère', which represents a mean of 14 000 births per year over the study period.

MATERIALS AND METHODS

Data on ETOPs were collected actively from medical records by a register of childhood deficiencies and adverse perinatal events in this county. Between 1989 and 2000, 996 ETOPs were notified.

RESULTS

Four main grounds for ETOPs were identified: (1) morphological anomalies with normal karyotype (39%), (2) chromosomal anomalies (35%), (3) other fetal grounds (16%), and (4) maternal indications (10%). Prevalence rates for the first two grounds increased significantly over the study period respectively from 2.0 to 2.9 and from 1.4 to 2.7 per 1000. Among the ETOPs carried out because of fetal indications, the percentage of late ETOPs (from 24 weeks of gestation) was 34.6%, and remained stable over the studied period. In some cases, a medical consensus was not reached with respect to indications for termination (sex chromosome anomalies, limb defects). We estimated the percentage of these cases as being 2.7% of the figure for fetal indications, without any variation in prevalence over the whole period (p = 0.59). The increasing number of ETOPs that occurred in the chromosomal aberrations group during the study period is thought to be due to an increase in diagnostic sensitivity. The increase that occurred in the morphological anomalies group is thought to be due both to an increase in sensitivity and to a widening of the field with respect to indications, some of which have an uncertain prognosis (e.g. agenesis of the corpus callosum).

CONCLUSION

This study provides useful data for monitoring medical practice consistency within the field of prenatal diagnosis, and for the drive to keep medical practice within ethically acceptable limits.

Sonographic Screening Examinations in Pregnancy

There is no consistent evidence of risk caused by sonographic examinations—neither biologic risk for the fetus nor increased use of health services as a result of ascertained conditions. There is also no consistent benefit to routine sonography in terms of important health outcomes. The use of fetal sonography to screen for anomalies reveals evidence that raises substantial concerns regarding interobserver variability. This might be expected when using a test for screening that requires considerable skill. The range of reported sensitivities underscores the disadvantages of performing sonography on a routine basis rather than on selected patients. Pretest counseling may identify a subset of women for whom screening may be effective in improving health outcomes.

Prenatal diagnosis of dysmorphic syndromes by routine fetal ultrasound examination across Europe

OBJECTIVES

Ultrasound scan in the mid-trimester of pregnancy is now a routine part of prenatal care in most European countries. The objective of this study was to evaluate the prenatal diagnosis of dysmorphic syndromes by fetal ultrasound examination.

METHODS

Data from 20 registries of congenital malformations in 12 European countries were included in the study.

RESULTS

There were 2454 cases with congenital heart diseases, 479 of which were recognized syndromes, including 375 chromosomal anomalies and 104 syndromes without chromosomal anomalies. Fifty-one of the 104 were detected prenatally (49.0%). One hundred and ninety-two of 1130 cases with renal anomalies were recognized syndromes, including 128 chromosomal anomalies and 64 syndromes without chromosomal anomalies; 162 of them (84.4%) were diagnosed prenatally, including 109 chromosomal anomalies and 53 non-chromosomal syndromes. Fifty-four of the 250 cases with limb defects were recognized syndromes, including 16 chromosomal syndromes and 38 syndromes without chromosomal anomalies; 21 of these 54 syndromes were diagnosed prenatally (38.9%), including 9 chromosomal syndromes. There were 243 cases of abdominal wall defects including 57 recognizable syndromes, 48 with omphalocele and 9 with gastroschisis; 48 were diagnosed prenatally (84.2%). Twenty-six of the 187 cases with diaphragmatic hernia had recognized syndromes, including 20 chromosomal aberrations and 6 syndromes without chromosomal anomalies. Twenty-two of them (84.6%) were detected prenatally. Sixty-four of 349 cases with intestinal anomalies were recognized syndromes; 24 were diagnosed prenatally (37.5%). There were 553 cases of cleft lip and palate (CL(P)) and 198 of cleft palate (CP) including 74 chromosomal anomalies and 73 recognized non-chromosomal syndromes. Prenatal diagnosis was made in 51 cases of CL(P) (53.7%) and 7 of CP (13.7%). Twenty-two of 188 anencephalic cases were syndromic and all were diagnosed prenatally. Of 290 cases with spina bifida, 18 were recognized syndromes, and of them 17 were diagnosed prenatally. All 11 syndromic encephaloceles were diagnosed prenatally.

CONCLUSIONS

Around 50% of the recognized syndromes which are associated with major congenital anomalies (cardiac, renal, intestinal, limb defects, abdominal wall defects and oral clefts) can be detected prenatally by the anomaly scan. However the detection rate varies with the type of syndrome and with the different countries' policies of prenatal screening.

Increased nuchal translucency and congenital heart defects in a low-risk population

OBJECTIVE

Increased first-trimester nuchal translucency (NT) is a possible marker for congenital heart defects in euploid fetuses. In this study, we wanted to determine the sensitivity for congenital heart defects using the 95th centile of the NT as a cut-off point.

METHODS

All women who booked for delivery in our hospital in the first trimester underwent NT measurement at a crown-rump length (CRL) of between 35 and 75 mm. In all euploid fetuses and newborns with isolated or associated CHD, NT was examined retrospectively and classified as normal (<95th centile according to CRL-dependent centiles in our own data) or increased (> or =95th centile).

RESULTS

From a total of 12,978 euploid fetuses screened, 27 had CHD (22 isolated and 5 cases associated with additional malformations). Moreover, 7 of the 27 fetuses also had increased NT (26%). Increased NT was significantly more frequent in fetuses with associated CHD (4/5) than in those with isolated CHD (3/22, Yates corrected chi2 p=0.012). In fact, the relative risk for CHD was 6.6 times higher in fetuses with increased NT compared to those with normal NT.

CONCLUSION

Increased NT for the detection of CHD performed less well than in other studies. Nevertheless, it can be used as an indication for fetal echocardiography.

Comparison of two-dimensional and three-dimensional sonography in evaluating fetal malformations

PURPOSE

We assessed the differences between 2-dimensional (2D) and 3-dimensional (3D) sonography (US) in evaluating fetal malformations.

METHODS

Both 2D US and 3D US were used to examine pregnant women whose fetuses had malformations. The diagnostic information provided by the modalities was evaluated and compared.

RESULTS

A total of 62 malformations were confirmed by postnatal or postmortem follow-up in 41 fetuses of 40 pregnant women. 2D US made a definite and correct diagnosis of 49 malformations (79%), whereas 3D US definitely diagnosed 58 malformations (94%) (p < 0.01). 3D US definitely diagnosed all the abnormalities in 38 fetuses (93%), whereas 2D US did so in only 32 fetuses (78%) (p < 0.05). In 35 (60%) of the 58 malformations revealed by both 3D US and 2D US, the former provided more diagnostic information than the latter. 3D US was particularly superior to 2D US in evaluating fetal malformations of the cranium and face, spine and extremities, and body surface.

CONCLUSIONS

In comparison with 2D US, 3D US improves the diagnostic capability by offering more diagnostic information in evaluating fetal malformations, particularly in displaying fetal malformations of the cranium and face, spine and extremities, and body surface. 3D US is a valuable adjunct to 2D US in prenatal diagnosis.

EFSUMB: safety tutorial: epidemiology of diagnostic ultrasound exposure during pregnancy-European committee for medical ultrasound safety (ECMUS)

The present paper summarizes some of the epidemiological studies of in utero ultrasound exposure and subsequent childhood development. Emphasis is placed on birth weight, childhood malignancies, neurological development, handedness and speech development. The epidemiological evidence does not indicate any association between diagnostic ultrasound exposure during pregnancy and reduced birth weight, childhood malignancies or neurological development. However, a statistically significant association between ultrasound and left-handedness among males has been found in three studies. Thus, there is still need for more research.

Prenatal ultrasonographic detection of gastrointestinal obstruction: results from 18 European congenital anomaly registries

OBJECTIVES

We evaluated the prenatal detection of gastrointestinal obstruction (GIO, including atresia, stenosis, absence or fistula) by routine ultrasonographic examination in an unselected population all over Europe.

METHODS

Data from 18 congenital malformation registries in 11 European countries were analysed. These multisource registries used the same methodology. All fetuses/neonates with GIO confirmed within 1 week after birth who had prenatal sonography and were born during the study period (1 July 1996 to 31 December 1998) were included.

RESULTS

There were 670 793 births in the area covered and 349 fetuses/neonates had GIO. The prenatal detection rate of GIO was 34%; of these 40% were detected < or = 24 weeks of gestation (WG). A total of 31% (60/192) of the isolated GIO were detected prenatally, as were 38% (59/157) of the associated GIO (p=0.26). The detection rate was 25% for esophageal obstruction (31/122), 52% for duodenal obstruction (33/64), 40% for small intestine obstruction (27/68) and 29% for large intestine obstruction (28/95) (p=0.002). The detection rate was higher in countries with a policy of routine obstetric ultrasound. Fifteen percent of pregnancies were terminated (51/349). Eleven of these had chromosomal anomalies, 31 multiple malformations, eight non-chromosomal recognized syndromes, and one isolated GIO. The participating registries reflect the various national policies for termination of pregnancy (TOP), but TOPs after 24 WG (11/51) do not appear to be performed more frequently in countries with a liberal TOP policy.

CONCLUSION

This European study shows that the detection rate of GIO depends on the screening policy and on the sonographic detectability of GIO subgroups.

Congenital anomalies and first life year surveillance in Type 1 diabetic births

AIMS

To evaluate the rate of congenital anomalies (CA) and the reasons for mortality from 22 weeks of gestation until 1 year of age in births by Type 1 diabetic mothers.

METHODS

Population-based cohort study using combined data from four national health registers in Finland during 1991-1995, including 954 singleton pregnancies complicated by Type 1 diabetes.

RESULTS

Sixty births (629/10 000) involved registered major CA, of which 68% (n = 41) were isolated and 22% (n = 13) multiple anomalies, and in six cases, a syndrome was diagnosed (10%). After the exclusion of syndromes, the total number of anomalies was 73. Of the malformed infants, 63% were boys. The total rate of deaths among births until 1 year of age was higher in diabetic than in non-diabetic mothers (19.9/1000 vs. 8.1/1000): especially the rates of stillborns (odds ratio 2.4; 95% confidence interval 1.2-4.7) and post-neonatal deaths (3.8; 1.6-9.2) were higher. Of perinatal mortality (PNM) from the 22nd gestational week to the age of 7 days (13.6/1000), 23% were due to CA, 23% to prematurity, and the rest were intrauterine, mostly unexplained, deaths. Respiratory distress syndrome was the main cause of death among infants.

CONCLUSIONS

The rate of CAs in Type 1 diabetic pregnancies is still high, but their proportion as a cause of PNM has decreased. Though PNM rate was low, post-neonatal mortality was significantly increased, reflecting the shift of deaths from the perinatal period to a later age.

Evaluation of 239 cases of perinatal death using a fundamental classification system

OBJECTIVE

To classify 239 cases of perinatal death in a newly introduced classification system for underlying causes of perinatal death.

DESIGN

Prospective, descriptive.

SETTING

Dutch healthcare region Delft-Westland-Oostland (DWO).

MATERIALS AND METHODS

In 10 years (1983-1992), all cases of perinatal death with a birthweight above 500 g (n=239) were included into the study. We used a classification model based upon the underlying cause of death using simple principles of obstetrical and neonatal pathology. A team consisting of a gynaecologist, neonatologist and pathologist classified all cases of perinatal death into seven groups to determine the "most-probable" cause of death.

RESULTS

Birth trauma was seen in two cases (0.8%). Infections were seen in 16 cases (6.8%). Acute/subacute placental pathology in 77 cases (32.2%) and chronic placental pathology in 50 cases (21%). Bloodtype antagonism was seen in two cases (0.8%). Lethal congenital malformations in 55 cases (23%). Complications of pre-viable delivery in 20 cases (8.4%). Unclassifiable were 17 cases (7%): two cases could not be classified despite thorough investigation (1%) and 15 cases were lost for follow-up (6%).

CONCLUSIONS

Classification of perinatal death causes by using our fundamental classification system gives insight in the possible underlying causes of death. The results of such a classification can be used as guidelines for preventive measures in the future.

Realtime fetal ultrasound by telemedicine in Queensland. A successful venture?

We have established a realtime fetal tele-ultrasound consultation service in Queensland, which has been integrated into our routine clinical practice. The service, which uses ISDN transmission at 384 kbit/s, allows patients in Townsville to be examined by subspecialists in Brisbane, 1500 km away. For the 90 tele-ultrasound consultations performed for the first 71 patients, 90% of the babies have been delivered, and outcome data have been received on all the pregnancies. All significant anomalies and diagnoses have been confirmed. The referring clinicians would have physically referred 24 of the 71 patients to Brisbane in the absence of telemedicine. A crude cost-benefit calculation suggests that the tele-ultrasound service resulted in a net saving of A$6340, and at the same time enabled almost four times the number of consultations to be carried out.

Prenatal diagnosis of cleft lip and palate: detection rates, accuracy of ultrasonography, associated anomalies, and strategies for counseling

OBJECTIVE

As ultrasound becomes more widely utilized in pregnancy and imaging technology improves, cleft lip and palate will become more commonly identified in prenatal life. In efforts to meet the needs for information regarding cause and management, pregnant women and their partners are increasingly referred to cleft and craniofacial treatment programs. This group of patients provides unique challenges to professionals unfamiliar with the issues inherent to this population. Information regarding the extent of the defect and the absence of associated abnormalities is usually incomplete. Treatment teams may be uncomfortable with the possibility that couples may choose not to continue a pregnancy on the basis of what they hear. Currently between 14% and 25% of cleft lip, with or without cleft palate, is detected antenatally. About 12% of presumably isolated clefts will be one feature in a broader pattern of malformation. This article reviews the current status of ultrasound in the detection of clefts during pregnancy and outlines a strategy for counseling based on the author's experience in both a prenatal diagnosis program and a cleft-craniofacial treatment team.

Routine ultrasound screening in diabetic pregnancies

OBJECTIVES

To assess the detection rate of congenital fetal malformations and specific problems related to routine ultrasound screening in women with pre-existing diabetes.

METHODS

A retrospective study was carried out to assess the performance of routine ultrasound screening in women with pre-existing diabetes (Types 1 and 2) within a tertiary institution. The incidence, type and risk factors for congenital fetal malformations were determined. The detection rate of fetal anomalies for diabetic women was compared with that for the low-risk population. Factors affecting these detection rates were evaluated.

RESULTS

During the study period, 12 169 low-risk pregnant women and 130 women with pre-existing diabetes had routine ultrasound screening performed within the institution. A total of 10 major anomalies (7.7%) and three minor anomalies (2.3%) were present in the fetuses of the diabetic women. Central nervous system and cardiovascular system anomalies accounted for 60% of the major anomalies. Periconceptional hemoglobin A1c of more than 9% was associated with a high prevalence of major anomalies (143/1000). Women who had fetuses with major anomalies had a significantly higher incidence of obesity (78% vs. 37%; P < 0.05). Ultrasound examination of these diabetic pregnancies showed high incidences of suboptimal image quality (37%), incomplete examinations, and repeat examinations (17%). Compared to the 'low-risk' non-diabetic population from the same institution, the relative risk for a major congenital anomaly among the diabetic women was 5.9-fold higher (95% confidence interval, 2.9-11.9). The detection rate for major fetal anomalies was significantly lower for diabetic women (30% vs. 73%; P < 0.01), and the mean body mass index for the diabetic group was significantly higher (29 vs. 23 kg/m2; P < 0.001).

CONCLUSION

The incidence of congenital anomalies is higher in diabetic pregnancies. Unfortunately, the detection rate for fetal anomalies by antenatal ultrasound scan was significantly worse than that for the low-risk population. This is likely to be related to the maternal body habitus and unsatisfactory examinations. Methods to overcome these difficulties are discussed.

Implications of antenatal ultrasound screening in the incidence of major genitourinary malformations

Over the past 3 decades, infant mortality has decreased nearly 50%. Although neonatal intensive care deserves much of the credit, the recent increase in prenatal ultrasonography use, from 33% of pregnancies in 1980 to 78% in 1987, has improved early detection. The authors wished to evaluate the impact on major genitourinary malformations. Data obtained from the Malformations Surveillance Program at Brigham and Women's Hospital between 1974 and 1994, tracked 163,431 pregnancies and termination rates of fetuses with spina bifida, bladder exstrophy, prune belly syndrome, and posterior urethral valves. Hospital data showed 65% of fetuses with spina bifida, 46% with posterior urethral valves, 31% with prune belly syndrome, and 25% with exstrophy, were terminated electively. Clearly, surveillance programs and improved accuracy of antenatal ultrasound has allowed early diagnosis of major genitourinary malformations. Many factors influence decision making in these affected fetuses, including the financial and emotional impact of these major anomalies over a lifetime. Future societal decisions, and the reduction in these anomalies may influence our training programs, manpower needs, medical facility requirements, and the character of our practices. These findings may have significant implications in the field of pediatric urology.

Sinistrality--a side-effect of prenatal sonography: a comparative study of young men

Although ultrasound during pregnancy is used extensively, there is little published on adverse fetal effects. We undertook a cohort study including men born in Sweden from 1973 to 1978 who enrolled for military service. We estimated relative risks for being born left-handed according to ultrasound exposure in fetal life using logistic regression analysis. Eligible for the study were 6,858 men born at a hospital that included ultrasound scanning in standard antenatal care (exposed) and 172,537 men born in hospitals without ultrasound scanning programs (unexposed). During the introduction phase (1973 to 1975) there was no difference in left-handedness between ultrasound exposed and unexposed (odds ratio = 1.03, 95% confidence interval (CI) = 0.91 to 1.17). When ultrasonography was offered more widely (1976 to 1978), the risk of left-handedness was higher among those exposed to ultrasound compared with those unexposed (odds ratio = 1.32, 95% CI = 1.16 to 1.51). We conclude that ultrasound exposure in fetal life increases the risk of left-handedness in men, suggesting that prenatal ultrasound affects the fetal brain.