National Prenatal Screening Program Research Articles

Pregnant people's views and knowledge on prenatal screening for fetal trisomy in the absence of a national screening program.

Multiple non-invasive prenatal tests (NIPT) are available to screen for risk of fetal trisomy, however, there is no national prenatal screening program in Republic of Ireland. This study aimed to analyze pregnant people's opinions on availability, cost, and knowledge of NIPT for fetal aneuploidy. An anonymous questionnaire on prenatal screening tests and termination of pregnancy was distributed to patients attending antenatal clinics at a tertiary hospital. Descriptive analyses and chi-squared tests were completed. Among respondents, 62% (200/321) understood the scope of prenatal screening tests, with 77% (251/326) and 76% (245/323) correctly interpreting low- and high-risk test results, respectively. Only 26% (83/319) of participants had heard of NIPT. Chi-square tests showed a higher proportion of these people were ≥40 years old (p-value, <0.001), had post-graduate education (p-value, <0.001), or attended private clinics (p-value <0.001). Over 91% (303/331) of participants said every pregnant person should be offered prenatal screening tests for aneuploidy and 88% (263/299) believed these should be free. While pregnant Irish individuals have reasonable understanding of screening test interpretation, most were unaware of screening options. Additionally, participants' views on availability and associated cost of tests show the need for a national prenatal screening program, including education on fetal aneuploidy. These findings have relevance for countries without screening policies and are pertinent for broader maternity services.

The influence of the introduction of a national prenatal screening program on late termination of pregnancy, a retrospective cohort study.

To assess the influence of a national prenatal screening program on category 1 (lethal anomalies) late terminations of pregnancy (LTOP). In this population-based retrospective cohort study, we included all category 1 LTOPs from 2004 to 2015 in the Netherlands. The number of LTOPs before and after the introduction of the program was compared as well as the diagnostic process and factors contributing to LTOP. In total, 97 LTOPs were reported. After the introduction of the program, the number of LTOPs decreased from 17 per year to 5 per year on average. The number of cases in which the diagnostic process started with obstetric indications decreased from 55% to 17% (p<0.01) and the number of cases detected by routine screening increased from 11% to 52% (p<0.01). Four factors still contributed to LTOP after the introduction of the screening program: diagnostic or parental delay (40%), absence of screening (24%), false negative results of prior screening (14%) and late onset of disease (12%). The number of LTOPs decreased after the introduction of the screening program. At present, the diagnostic process is mostly screening driven. Parental- and diagnostic delay is still an important factor that contributes to LTOP.

Impact of a prenatal screening program on the Down syndrome phenotype: An interrupted time series analysis.

We hypothesized that children with Down syndrome who were born after the implementation of first-trimester combined screening for trisomy 13, 18, and 21 and a second-trimester ultrasound scan in Denmark would show a milder syndrome phenotype. We investigated the birth biometry, prevalence of congenital malformations, and early childhood morbidity of children with Down syndrome before and after implementation of this screening program. A nationwide register-based study of all live born singletons with Down syndrome in Denmark from 1995 to 2018. In interrupted time series analyses, we studied the temporal developments in birth biometry, prevalence of congenital malformations, and early childhood morbidity related to the implementation of a national prenatal screening program. We included 602 singletons with Down syndrome born before and 308 after implementation of the screening program. Z-scores of birthweight and head circumference increased over time before screening, but this temporal development changed after implementation by -0.05 (95% confidence interval [CI]: -0.11 to 0.01) and -0.05 (95% CI -0.12 to 0.02), respectively. Just after implementation, the prevalence of non-severe congenital heart disease decreased (relative change in odds 0.48 [95% CI: 0.24-0.94]). For severe congenital heart disease, atrioventricular septal defect, and non-heart malformations, this change was 1.16 (95% CI: 0.56-2.41), 0.95 (95% CI: 0.43-2.03), and 0.98 (95% CI: 0.33-2.76), respectively. For all malformations, pre-existing temporal developments did not change following implementation of screening. The implementation was associated with higher odds of admission to a neonatal intensive care unit (relative change 1.98 [95% CI: 0.76-5.26]) and an increased risk of hearing impairment (risk difference 3.4% [95% CI: -0.4% to 7.1%]). In contrast, the implementation was not associated with the incidence of hospital admissions by 2 years of age or with the probability of a thyroid disorder. After implementation of a national prenatal screening program, we did not observe a milder Down syndrome phenotype apart from an apparent reduction in the proportion of children with non-severe congenital heart disease; this result is, however, limited by small numbers.

Modeling Future Blood Requirements in Patients with Transfusion-Dependent β-Thalassemia in Greece

Introduction: In Greece, official data confirm that blood supply is consistently declining, primarily because of decreased voluntary blood donations. At this rate, it is unclear whether there will be sufficient red blood cell (RBC) units to meet future demand for patients with β-thalassemia. We modeled future blood demand in patients with transfusion-dependent β-thalassemia (TDT) over the next 15 years to assess whether such a demand can be met.Methods: A discrete time, stochastic, individual-based model, was developed to assess future blood needs of patients with TDT in Greece. The model adopted a cohort approach and patients enter the model shortly after birth and exit at death. The model was seeded with data from the National Registry for Hemoglobinopathies in Greece (NRHG; patient population) and data from the National Blood Centre (RBC units) (Table). To quantify the decrease in TDT incidence, a linear regression model was fitted to the incident cases as described by Voskaridou (Voskaridou E, et al. Ann Hematol 2019;98:55-66). The calculated annual reduction rate was then applied to the observed thalassemia major (TM) and thalassemia intermedia (TI) incident cases for 2012 (Voskaridou E, et al. Ann Hematol 2012;91:1451-1458). The model assumes the reduction would continue through to 2020, from which time the incidence curve would be constant.Results: The model estimates a decrease in both target population, primarily due to the implementation of the national prenatal screening program and TM related mortality, (9.2%, 18.6%, and 26.0% in 2025, 2030, and 2034, respectively) and in demand for RBC units (100,665, 89,428 and 80,565, respectively) over the next 15 years. After accounting for any blood donated, based on latest (2017) data as projected to 2020, Greece is expected to be short of 56,716 RBC units to meet needs of patients with TDT in 2020. By 2025, 2030, and 2034, cumulative required RBC units for patients with TDT are estimated to be 307,150, 501,698, and 617,074, respectively. Assuming RBC units are divided among patients ≥ 18 years and those < 18 years in line with the population mix in the NRHG, cumulative RBC units required for adult patients with TDT are estimated to be 292,837, 464,337, and 554,083 by 2025, 2030, and 2034, respectively.Conclusions: Though blood demand for patients with TDT is expected to decrease in line with a decrease in the patient population, it will remain a challenge for the healthcare system in Greece to meet the demand, primarily due to a continuing shortage of available RBC units from voluntary donations. This annual deficit is estimated to accumulate to over 600,000 units over the next 15 years. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Uptake of fetal aneuploidy screening after the introduction of the non-invasive prenatal test: A national population-based register study.

IntroductionThe introduction of the non‐invasive prenatal test (NIPT) has shifted the prenatal screening landscape. Countries are exploring ways to integrate NIPT in their national prenatal screening programs, either as a first‐ or second‐tier test. This study aimed to describe how the uptake of fetal aneuploidy screening changed after the introduction of NIPT as a second‐tier and as a first‐tier test within the national prenatal screening program of the Netherlands.Material and methodsA population‐based register study in the Netherlands, recording uptake of fetal aneuploidy screening. Data from all pregnant women choosing to have the first‐trimester combined test (FCT) or first‐tier NIPT between January 2007 and March 2019 were retrospectively collected using national registration systems. Uptake percentages for fetal aneuploidy screening (FCT and NIPT) were calculated and stratified by region and maternal age. Statistical significance was determined using trend analysis and chi‐squared tests.ResultsBetween 2007 and 2013 FCT uptake increased from 14.8% to 29.5% (P = .004). In April 2014 NIPT was introduced as a second‐tier test for high‐risk women after FCT (TRIDENT‐1 study). FCT uptake rose from 29.5% in 2013 to 34.2% in 2015 (P < .0001). After the introduction of NIPT as a first‐tier test for all women in April 2017 (TRIDENT‐2 study), FCT uptake declined significantly from 35.8% in 2016 to 2.6% in 2018 (P < .0001). NIPT uptake increased to 43.4% in 2018. Regionally, NIPT uptake ranged from 31.8% to 67.9%. Total uptake (FCT and NIPT) between 2007 and 2018 increased significantly from 14.8% to 45.9% (P < .0001). However, total uptake stabilized at 46% for both years of TRIDENT‐2 (April 2017‐March 2019).ConclusionsAn increase in total fetal aneuploidy screening uptake up to 45.9% was observed after the introduction of NIPT. Uptake appears to have stabilized within a year after introducing first‐tier NIPT.

In-house genetic counseling increases the detection of abnormal karyotypes\u2014a 26-year experience in prenatal diagnosis in a single tertiary referral hospital in Poland

PurposeTo evaluate the trends in prenatal diagnosis over 26 years in a tertiary referral hospital.MethodsA retrospective analysis of invasive prenatal procedures performed between 1991 and 2016. Maternal characteristics, indications for invasive diagnosis, and percentage of abnormal karyotypes were compared between periods according to guidelines implemented nationally and locally.ResultsA total of 14,302 invasive prenatal procedures were performed. The proportion of invasive procedures performed for advanced maternal age, abnormal karyotype in a previous pregnancy, and maternal anxiety decreased from 71.1%, 17.8%, 8.9% in 1991 to 23.9%, 1.3%, and 2.3% in 2016 (OR 0.6, 0.8, and 0.9 for each 5 years, respectively; p < 0.001), while the proportion of invasive procedures performed for abnormal ultrasound increased from 2.2% in 1991 to 51.6% in 2016 (OR 1.9 for each 5 years; p < 0.001). Abnormal karyotype was found in 9.7%. The proportion of abnormal karyotypes increased significantly from 0.0% in 1991 to 15.7% in 2016 (OR 1.35 for each 5-year period; p < 0.001). The odds of abnormal karyotype increased after the implementation of the Ordinance of the Minister of Health in 2003 (OR 1.6), the National Prenatal Screening Program in 2007 (OR 2.2), and the in-house genetic counseling with combined first trimester screening in 2015 (OR 3.1).ConclusionsSignificant changes in prenatal diagnosis led to a better selection of patients undergoing invasive prenatal procedures. The implementation of in-house genetic counseling was associated with an increased rate of the detection of abnormal karyotypes.

Use of alternative medicine, ginger and licorice among Danish pregnant women \u2013 a prospective cohort study

BackgroundThe use of alternative medicines and dietary supplements is constantly changing, as are dietary habits. One example of this phenomenon is the current popularity of ginger products as an everyday health boost. Ginger and licorice has also been shown to ameliorate nausea a common complaint in early pregnancy. Alternative medicines are often regarded as safe. However, they might affect fetal development, such as through alterations of hormone metabolism and cytochrome P450 function. Health care professionals may be unaware of the supplementation habits of pregnant women, which may allow adverse exposures to go unnoticed, especially if the rates of use in pregnancy are not known. We therefore investigated the use of alternative medicines and licorice among pregnant Danish women.MethodsA total of 225 pregnant women were included in a prospective cohort when attending the national prenatal screening program at gestational weeks 10–16. Participants were asked to complete a questionnaire regarding their socio-economic status and lifestyle habits, including their intake of alternative medicine and licorice.ResultsWe found that 22.7% of women reported taking alternative medicines, with 14.7% reporting daily consumption. Ginger supplements were consumed by 11.1%, mainly as health boost and 87.1% reported consumption of licorice. Regular or daily licorice consumption was reported by 38.2 and 7.1%, respectively. Notably, the use of licorice was reflected by an increase in blood pressure of the pregnant women.ConclusionsThe use of licorice and alternative medicines appears to be common in pregnant Danish women, supporting the need for further investigations into the safety of alternative medicine use during pregnancy and the importance of up-to-date personalized counseling regarding popular health trends and lifestyle habits.

Special Issue: Abstracts of the ISPD 22nd International Conference on Prenatal Diagnosis and Therapy, Antwerp, Belgium, 8-11 July 2018.

Objectives: In most countries, non-invasive prenatal testing (NIPT) has been introduced commercially without any governmental guidance. In the Netherlands, prenatal screening for fetal anomaly is subject to a governmental license. NIPT has been implemented as part of the TRIDENT studies (Trial by Dutch laboratories for Evaluation of NIPT). TRIDENT-2 aims at offering NIPT to all pregnant women (∼174,000 women/year) within the national prenatal screening program. Since April 2017, women can choose NIPT as a contingent test after first-trimester combined testing (FCT), but may also choose NIPT as first-tier screening test. TheTRIDENT studies evaluate implementation and women's perspectives. Methods: All pregnant women in the Netherlands are offered prenatal screening and are counselled by certified counselors, generally midwives. A first-tier NIPT costs women € 175, comparable to the costs of FCT (∼€ 168). NIPT is performed by three Dutch university clinical genetic laboratories using an in-house validated test. Women can choose to have analysis of chromosomes 21, 18, and 13 without or with a report of incidental findings (findings other than trisomy 21, 13, 18) on the remaining autosomes, respectively, using the 'targeted' or 'whole genome' WISECONDOR pipeline. Sex chromosomes are not analyzed. Results: After 8 months of study, 48,234 tests have been performed (nationwide uptake of prenatal screening by NIPT as first-tier test was 40%), and 98.3% reports successfully issued. Failure rate was less than 2%. Mean turnaround time was 7 working days. 80% of women chose to have all autosomes analyzed. A total of 152 cases of T21 (0.3%), 32 cases of T18 (0.1%), 41 cases of T13 (0.1%), and 158 (0.3%) other chromosomal aberrations were found. First year results (and available follow-up) will be presented at the meeting. Conclusions: The Netherlands are the first country where NIPT is incorporated as a first-line test into a governmentally supported and health care funded prenatal aneuploidy screening program. The incorporation of the test in a university hospital laboratory and clinical service guarantees appropriate counselling and allows for proper follow-up. This 3-year study aims to provide all necessary information for a successful introduction of NIPT within the Dutch National prenatal screening program.

Congenital toxoplasmosis in Austria: Prenatal screening for prevention is cost-saving.

BackgroundPrimary infection of Toxoplasma gondii during pregnancy can be transmitted to the unborn child and may have serious consequences, including retinochoroiditis, hydrocephaly, cerebral calcifications, encephalitis, splenomegaly, hearing loss, blindness, and death. Austria, a country with moderate seroprevalence, instituted mandatory prenatal screening for toxoplasma infection to minimize the effects of congenital transmission. This work compares the societal costs of congenital toxoplasmosis under the Austrian national prenatal screening program with the societal costs that would have occurred in a No-Screening scenario.Methodology/Principal findingsWe retrospectively investigated data from the Austrian Toxoplasmosis Register for birth cohorts from 1992 to 2008, including pediatric long-term follow-up until May 2013. We constructed a decision-analytic model to compare lifetime societal costs of prenatal screening with lifetime societal costs estimated in a No-Screening scenario. We included costs of treatment, lifetime care, accommodation of injuries, loss of life, and lost earnings that would have occurred in a No-Screening scenario and compared them with the actual costs of screening, treatment, lifetime care, accommodation, loss of life, and lost earnings. We replicated that analysis excluding loss of life and lost earnings to estimate the budgetary impact alone.Our model calculated total lifetime costs of €103 per birth under prenatal screening as carried out in Austria, saving €323 per birth compared with No-Screening. Without screening and treatment, lifetime societal costs for all affected children would have been €35 million per year; the implementation costs of the Austrian program are less than €2 million per year. Calculating only the budgetary impact, the national program was still cost-saving by more than €15 million per year and saved €258 million in 17 years.Conclusions/SignificanceCost savings under a national program of prenatal screening for toxoplasma infection and treatment are outstanding. Our results are of relevance for health care providers by supplying economic data based on a unique national dataset including long-term follow-up of affected infants.

Prevalence, timing of diagnosis and pregnancy outcome of abdominal wall defects after the introduction of a national prenatal screening program.

To examine prevalence, time of diagnosis and outcome of fetuses with an exomphalos or gastroschisis, diagnosed since the introduction of a national prenatal screening program in 2007. A prospective cohort study was undertaken in two fetal medicine units in the Netherlands. Cases were included if the estimated due date was between 2009 and 2013. Outcome measures were gestational age at diagnosis, presence of additional anomalies and pregnancy outcome. A total of 141 exomphalos and 44 gastroschisis cases were included in the study, of which, respectively, 96 and 95% were diagnosed prenatally. The majority of the cases are visualized prior to the 20-week scan. In the exomphalos group, 83% had additional anomalies of which 57% had a chromosomal anomaly. Additional anomalies were present in 11% of the gastroschisis cases of which 40% had a chromosomal anomaly. The pregnancy termination rate was 61% (exomphalos) and 14% (gastroschisis). Almost all exomphalos and gastroschisis cases are diagnosed prenatally, the majority in the first trimester. Associated anomalies are far more common in exomphalos with a fourfold lower survival rate than gastroschisis. In the exomphalos group, the pregnancy termination rate doubled, while in the gastroschisis group the rate remained low. © 2017 John Wiley & Sons, Ltd.

An Audit of Second-Trimester Fetal Anomaly Scans Based on a Novel Image-Scoring Method in the Southwest Region of the Netherlands

Since 2007 the second-trimester fetal anomaly scan is offered to all pregnant women as part of the national prenatal screening program in the Netherlands. Dutch population-based screening programs generally have a well-described system to achieve quality assurance. Because of the absence of a uniform system to monitor the actual performance of the fetal anomaly scan in 2012, we developed a standardized image-scoring method. The aim of this study was to evaluate the scanning performance of all sonographers in the southwestern region of the Netherlands using this image-scoring method. Each sonographer was requested to set up a digital portfolio. A portfolio consists of five logbooks from five different pregnant women, each containing 25 fetal anatomical structures and six biometric measures of randomly selected fetal anomaly scans. During the study period, 425 logbooks of 85 sonographers were assessed as part of the audit process. Seventy-three out of 85 sonographers (86%) met the criteria in the primary audit, and 12 sonographers required individual hands-on training. A successful assessment was achieved for 11 sonographers in the re-audit and one sonographer ceased her contract. Moreover, 2.1% of the required images were not digitally stored and therefore could not be reviewed. Quality assessment using the image-scoring method demonstrated that most of the sonographers met the expectations of the audit process, but those who had subpar performance met the expectations after retraining.

Only a minority of sex chromosome abnormalities are detected by a national prenatal screening program for Down syndrome.

How does a national prenatal screening program for Down syndrome (DS) perform in detecting sex chromosome abnormalities (SCAs)-Turner syndrome (TS), Klinefelter syndrome, 47,XXX and 47,XYY syndromes. The SCA detection rate resulting from DS screening was below 50% for all four groups of SCAs. The detection rates of SCAs are higher in countries with DS screening. TS is associated with greater nuchal translucency (NT) and lower pregnancy-associated plasma protein-A (PAPP-A). However, specific detection rates of SCAs using prenatal DS screening have not been determined. No clear trend in PAPP-A, free beta human chorionic gonadotropin (β-hCG) and NT has been found in the remaining SCAs. Several lines of inquiry suggest that it would be advantageous for individuals with SCA to be detected early in life, leading to prevention or treatment of accompanying conditions. There is limited information about pre- and perinatal status that distinguishes SCA embryogenesis from normal fetal development. A register-based case-control study from the Danish Central Cytogenetic Register (DCCR), cross-linked with the Danish Fetal Medicine Database (DFMD), was performed from 2008 to 2012. Groups of SCAs were compared with DS and then matched with non-SCA controls to assess differences between these groups in prenatal markers and birth outcomes. We included cases with prenatal and post-natal SCA karyotypes (n = 213), DS (n = 802) and 168 056 controls. We screened 275 037 individuals examined prenatally. We retrieved information regarding maternal age, NT, β-hCG and PAPP-A, as well as details regarding maternal and newborn characteristics. The DS screening procedure detected 87 per 100 000 TS (42% of expected), 19 per 100 000 Klinefelter syndrome (13% of expected), 16 per 100 000 47,XXX (16% of cases) and 5 per 100 000 47,XYY (5% of expected) SCAs, with an overall detection rate of 27%. Compared with controls, all four SCA groups showed significantly higher NT and lower PAPP-A compared with controls (all P < 0.01) and similar to DS. The legal abortion rate was high for all four syndromes (47,XXX: 24%; 47,XYY: 29%; Klinefelter syndrome: 48%, TS: 84%). For SCA fetuses carried to term, only TS fetuses had consistently lower birthweights and placenta weights than non-SCA controls (both P = 0.0001). A few SCA cases localized in DCCR could not be found in DFMD (n = 16). Controls were matched on sex of the fetus of cases, meaning that all electively aborted fetuses (before week 12) were excluded, possibly reducing the diversity in the control group. We were not able to localize all diagnosed cases of SCA and DS in DFMD. Although these cases were present in DCCR, we were not able to account for the discrepancy. In addition, we suspect that several SCA children have not been diagnosed yet and future post-natal diagnosis of these cases would reduce the diagnostic yield reported here even further. The prenatal detection rate is below 50% for all SCAs. The approach used for detecting DS cannot be extended to also include SCAs. In addition, all SCAs have low PAPP-A and increased NT, thus probably reflecting an abnormal embryogenesis. Growth retardation of TS fetuses is if anything more pronounced than previously reported, both when evaluating fetus and placenta. This study received support from Aarhus University and the Novo Nordisk Foundation. The authors have no competing interests that may be relevant to the study.

Prenatal detection of congenital heart disease--results of a national screening programme.

Congenital heart disease (CHD) is the most common congenital malformation and causes major morbidity and mortality. Prenatal detection improves the neonatal condition before surgery, resulting in less morbidity and mortality. In the Netherlands a national prenatal screening programme was introduced in 2007. This study evaluates the effects of this screening programme. Geographical cohort study. Large referral region of three tertiary care centres. Fetuses and infants diagnosed with severe CHD born between 1 January 2002 and 1 January 2012. Cases were divided into two groups: before and after the introduction of screening. Detection rates were calculated. The prenatal detection rate (n = 1912) increased with 23.9% (95% confidence interval [95% CI] 19.5-28.3) from 35.8 to 59.7% after the introduction of screening and of isolated CHD with 21.4% (95% CI 16.0-26.8) from 22.8 to 44.2%. The highest detection rates were found in the hypoplastic left heart syndrome, other univentricular defects and complex defects with atrial isomerism (>93%). Since the introduction of screening, the 'late' referrals (after 24 weeks of gestation) decreased by 24.3% (95% CI 19.3-29.3). This is the largest cohort study to investigate the prenatal detection rate of severe CHD in an unselected population. A nationally organised screening has resulted in a remarkably high detection rate of CHD (59.7%) compared with earlier literature.

Down syndrome screening information in midwifery practices in the Netherlands: Strategies to integrate biomedical information.

The aim of this qualitative study was to analyse counselling with regard to prenatal screening in midwifery consultations in the Netherlands where a national prenatal screening programme has only existed since 2007, after years of social and political debates. The methodology is based on in situ observations of 25 counselling consultations in four midwifery practices in two main cities in the Netherlands. The results of this study show that, since midwives are obliged to offer information on Down syndrome screening to all pregnant women (2007), they have to deal with the communication of medical screening information using biostatistical concepts to explain risks, calculations, probabilities and chromosomal anomalies. In order to avoid the risk of medicalization of their consultation, midwives develop strategies that allow them to integrate this new biomedical discourse while maintaining their low medicalized approach of midwife-led care. One of their main strategies is to switch from 'alarming' biomedical messages to 'reassuring words' in order to manage the anxiety induced by the information and to keep the control over their low medicalized consultation. They also tend to distance themselves from the obligation to talk about screening. The way midwives handle these counselling consultations allows them to respect their obligation to propose information, and to remain faithful to their struggle to protect the natural process of pregnancy as well as their professional autonomy.

Antibodies against Coxiella burnetii and pregnancy outcome during the 2007-2008 Q fever outbreaks in the Netherlands

BackgroundQ fever has become a major public health problem in the Netherlands. Infection with Coxiella burnetii (Q fever) during pregnancy has resulted in adverse pregnancy outcome in the majority of reported cases. Therefore, we aimed to quantify this risk by examining the earliest periods corresponding to the epidemic in the Netherlands.MethodsSerum samples that had been collected from the area of highest incidence by an existing national prenatal screening programme and data from the Netherlands Perinatal Registry (PRN) on diagnosis and outcome were used. We performed indirect immunofluorescence assay to detect the presence of IgM and IgG antibodies against C. burnetii in the samples. The serological results were analyzed to determine statistical association with recorded pregnancy outcome.ResultsEvaluation of serological results for 1174 women in the PRN indicated that the presence of IgM and IgG antibodies against phase II of C. burnetii was not significantly associated with preterm delivery, low birth weight, or several other outcome measures.ConclusionThe present population-based study showed no evidence of adverse pregnancy outcome among women who had antibodies to C. burnetii during early pregnancy.

Prenatal ultrasound screening of congenital heart disease in an unselected national population: a 21-year experience

ObjectiveTo determine the prevalence and spectrum of congenital heart disease (CHD) and the impact of a national prenatal ultrasound screening programme on outcome in a well-characterised population.Design and settingA comprehensive...

Cystic fibrosis: selecting the prenatal screening strategy of choice.

Cystic fibrosis is a serious disorder. Research into the treatment of affected individuals is in progress, but a cure is not expected in the near future. In this review, we demonstrate that prenatal screening for cystic fibrosis meets the requirements for a worthwhile screening programme. We explain the reasons that have led us to conclude that one approach ('couple screening') is the method of choice. The couple-based approach calls for reporting results to the couple as a unit. Only if both parents are found to be carriers is the result designated screen-positive and an amniocentesis or chorionic villus sampling offered. This offers a substantial reduction in the proportion of women with unaffected pregnancies with positive results (the false-positive rate) compared with other methods without reducing the detection of affected pregnancies. It also avoids creating a screen-positive group for which no definitive diagnosis is available. This is a problem with other screening methods. The couple method can achieve a 72% detection rate for a 0.1% false-positive rate. The screening method is simple, non-invasive, reliable, safe and reasonably cost effective. Existing programmes have shown that screening using this method is acceptable to health care professionals and patients. Setting up a national prenatal screening programme for cystic fibrosis is timely and should be implemented using the couple screening method.