[Show abstract][Hide abstract] ABSTRACT: From 1998 the population-based North of England Multiple Pregnancy Register (MPR) has collected data on all multiple pregnancies in the region from the earliest point of ascertainment in the pregnancy. This article describes the development of the MPR and the findings of the first 5 years of data collection. Mothers now give explicit consent for their inclusion with named data, in accordance with section 60 of the Health and Social Care Act 2001. During 1998 to 2002, 2310 twin pregnancies were registered, with an increasing twinning rate of 13.6 to 16.6 per 1000 maternities. Chorionicity ascertainment in twin maternities with at least one stillbirth or live birth has improved from 81% in 1998 to 91% in 2002. Before 24 weeks of gestation, 8.4% (359/4620) of fetuses were lost either spontaneously or as a result of termination of pregnancy. The perinatal mortality rate was much higher in monochorionic than dichorionic twins, mainly due to differences in stillbirth rates (49.0 vs. 11.5 per 1000 maternities respectively, risk rate = 4.2; 95% confidence intervals 2.7-6.6). The gestational-age-specific neonatal mortality rates were similar in twins and singletons, except in the group of term births (> or weeks' gestation) when compared by conventional gestational age categories. For stillbirths, the rates were even lower than in singletons in gestational age categories of less than 32 weeks. The register is an important resource of data on multiple pregnancies, which allows monitoring of trends in multiple birth rates and pregnancy losses and provides a unique opportunity for etiological and long-term follow-up studies.
Twin Research and Human Genetics 01/2007; 9(6):913-8. · 1.92 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To describe the impacts of participating in confidential enquiry panels for the Confidential Enquiry into Stillbirths and Deaths in Infancy.
Qualitative interview study.
The former northern health region of England.
Eighteen health professionals who had participated in at least one confidential enquiry panel.
Semistructured one-to-one interviews using purposive sampling; transcripts were analysed by identifying recurring themes. Data were organised and coded using NUD*IST.
Views on the impacts of participation on clinical practice and views on the strengths and limitations of confidential enquiries.
Participants valued attendance at panels as a learning experience that provoked reflection on their own clinical practice. Participants felt that taking part had a positive impact on their clinical thinking and practice by increasing their awareness of standards of care. These impacts occurred through both the detailed examination of cases and the interaction with colleagues from different disciplines and hospitals. Learning impacts were cascaded to colleagues through informal discussion and teaching. Concrete examples of changes in practice at the organisational level, stimulated by panel attendance, were reported.
The confidential enquiry approach was supported not only as an effective way of assessing care but also as a valuable learning experience that motivated change in clinical practice. Local benefits of nationally coordinated confidential enquiries should be valued and supported in their future development. Wide multidisciplinary participation in enquiry panels coordinated through regional clinical networks should be promoted.
BJOG An International Journal of Obstetrics & Gynaecology 05/2006; 113(4):387-92. · 3.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A regional population-based Multiple Pregnancy Register was established in 1998, with the aim of collecting detailed information on multiple pregnancies to enable research into mortality and morbidity in multiples. Multiple pregnancies are notified to the Register as soon as they are detected, irrespective of whether they resulted in a spontaneous abortion, termination of pregnancy or registered birth. Nine hundred and twenty-six twin pregnancies were recorded during 1998-99, giving a twinning rate of 14.8 per 1000 maternities (rate at birth 13.0 per 1000 maternities). Sixty one per cent of twin pregnancies were detected before 13 weeks of gestation. Chorionicity was determined in 82.6% of 849 twin maternities with at least one stillbirth or livebirth. The fetal loss rate before 24 weeks of gestation was 10.5% (194/1852). The perinatal and infant mortality rates were 40.6 per 1000 births and 32.6 per 1000 livebirths respectively. A prospective Multiple Pregnancy Register not only allows monitoring of trends in multiple birth rates and mortality, but also etiological research and long-term follow-up studies.
[Show abstract][Hide abstract] ABSTRACT: Using data from the Northern Congenital Abnormality Survey, we describe trends in the prevalence of neural tube defects (NTDs), maternal age-specific prevalence, outcome of pregnancy and the sensitivity of antenatal diagnosis of NTD-affected pregnancies in the Northern Region during 1984–96. This population-based sample consisted of 934 NTDs: there were 403 (43.1%) with anencephaly, 472 (50.5%) with spina bifida and 59 (6.3%) with encephalocele. The total prevalence at birth was 17.9 per 10 000 births and terminations (95% confidence interval [CI] = 16.7, 19.0) with a significant reduction over time (χ2 for trend = 7.2; P = 0.007). The overall birth prevalence was 5.6 per 10 000 births [95% CI = 5.0, 6.3]; there was also a significant reduction in birth prevalence with time (χ2 for trend = 68.3; P < 0.0001). Maternal age-specific prevalence rates decreased with increasing age. The proportion of NTD pregnancies terminated increased from 60.3% (325 cases) during 1984–90 to 78.6% (293 cases) during 1991–96, whereas the proportion of livebirths declined from 31.7% (171 cases) to 15.0% (56 cases) (P < 0.001). The sensitivity of antenatal diagnosis was consistently high for anencephaly (98%) and increased significantly for spina bifida from 60% during 1984–90 to 85% during 1991–96 (P < 0.05). Ascertainment of all cases of NTD in the Northern Region revealed a twofold reduction in birth prevalence between 1984–90 and 1991–96. This has resulted from improvements in the accuracy of antenatal detection of NTD-affected pregnancies with an increase in terminations of pregnancy.
[Show abstract][Hide abstract] ABSTRACT: To analyse data on cases with urological abnormalities recorded over a 15-year period (1984-98) by the Northern Region Congenital Abnormality Survey (NorCAS), with special reference to fetal renal pelvic measurements.
Data on all urological cases recorded in the NorCAS database and in notification documents forwarded from hospitals in the Northern Region were extracted and incorporated in a separate unattributable database for analysis. Specific fields for filing recorded fetal renal pelvic measurements with their corresponding gestational ages were inserted; it was ensured as far as possible that these measurements were made in the anteroposterior plane.
The total number of cases analysed was 2737; a measurement of the fetal renal pelvis was recorded in 813, and more than once in 468, giving 1301 measurement episodes with the corresponding gestational ages, pregnancy and postnatal outcome. The male/female (M/F) ratio was significantly higher in those cases which had a fetal renal pelvic measurement recorded than in those which had not. This was because there was a 12/1 M/F ratio in measured cases of vesico-ureteric reflux (VUR). Few cases of VUR had a fetal renal pelvic measurement recorded. The difference in the fetal renal pelvic measurements between those cases which were normal postnatally and those which had a structural abnormality, an obstructive lesion or VUR became significant at 7 mm and at 18 weeks of gestational age. Over the whole period the proportion of cases in which micturating cysto-urethrography was technically possible and might have contributed to the diagnosis was 28.5%; the highest was 44.1% in 1998.
Antenatal renal dilatation occurs infrequently in the presence of VUR and when it does, the fetus will probably be male. Antenatal ultrasonography is unlikely to contribute to detecting VUR in females, the gender in whom early diagnosis is particularly desirable. Other means of suspecting VUR antenatally, e.g. the family history or genetic coding, may be more valuable. A measurement of the fetal renal pelvis of > or = 7 mm at a gestational age of 18 weeks should prompt subsequent careful ultrasonography during the pregnancy and early postnatal investigation of the urinary tract. The diagnosis of VUR should not be excluded because the fetal renal pelvis is only minimally dilated if the fetus is female.
BJU International 03/2001; 87(4):376-80. · 3.13 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: 201 fetuses and babies with a congenital diaphragmatic herniation or eventration (referred to collectively as CDH) were notified to the Northern Region Congenital Abnormality Survey (NorCAS) in the 13-year period from 1985 to 1997, an incidence of 0.25 per 1000 births. The 1-year survival of all pregnancies associated with CDH was 37%. The 1-year survival of livebirths was 50%. Antenatal scan detected the diaphragmatic defect or associated structural abnormality in 50%. Another major structural abnormality was present in 62 (31%); one of these babies survived and 26 pregnancies were terminated. This group contained four of the six antepartum stillbirths, all three intrapartum stillbirths and four of the five spontaneous miscarriages. Non-isolated CDH occurred in association with Fryns (5), Goldenhar (1) and de Lange (1) syndromes, and in 16 of 17 with a chromosome anomaly. 53% of the 139 fetuses with isolated CDH survived to 1 year of age, and 59% of the 124 liveborn survived. Of 37 fetuses with isolated CDH detected before 25 weeks gestation, 12 pregnancies were terminated. There were 11 survivors among the 25 continuing pregnancies (44%). The overall survival of babies with CDH is very poor but, when a defect is identified by ultrasound before 25 weeks gestation, chromosome analysis and a careful ultrasound scan may suggest which fetuses have an isolated diaphragmatic abnormality and a greater chance of survival.
British Journal of Radiology 05/2000; 73(868):360-5. · 1.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Using data from the Northern Congenital Abnormality Survey, we describe trends in the prevalence of neural tube defects (NTDs), maternal age-specific prevalence, outcome of pregnancy and the sensitivity of antenatal diagnosis of NTD-affected pregnancies in the Northern Region during 1984-96. This population-based sample consisted of 934 NTDs: there were 403 (43.1%) with anencephaly, 472 (50.5%) with spina bifida and 59 (6.3%) with encephalocele. The total prevalence at birth was 17.9 per 10,000 births and terminations (95% confidence interval [CI] = 16.7, 19.0) with a significant reduction over time (chi(2) for trend = 7.2; P = 0.007). The overall birth prevalence was 5.6 per 10,000 births [95% CI = 5.0, 6.3]; there was also a significant reduction in birth prevalence with time (chi(2) for trend = 68.3; P < 0.0001). Maternal age-specific prevalence rates decreased with increasing age. The proportion of NTD pregnancies terminated increased from 60.3% (325 cases) during 1984-90 to 78.6% (293 cases) during 1991-96, whereas the proportion of livebirths declined from 31.7% (171 cases) to 15.0% (56 cases) (P < 0.001). The sensitivity of antenatal diagnosis was consistently high for anencephaly (98%) and increased significantly for spina bifida from 60% during 1984-90 to 85% during 1991-96 (P < 0.05). Ascertainment of all cases of NTD in the Northern Region revealed a twofold reduction in birth prevalence between 1984-90 and 1991-96. This has resulted from improvements in the accuracy of antenatal detection of NTD-affected pregnancies with an increase in terminations of pregnancy.
Paediatric and Perinatal Epidemiology 04/2000; 14(2):104-10. · 2.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To analyse urological cases registered with the Northern Congenital Abnormality Survey (NorCAS) and thus assess antenatal diagnostic sensitivity, measure regional interhospital variation and determine whether antenatal ultrasonography has contributed to the prevention of urinary tract disease in childhood.
All notification documents forwarded to NorCAS from its inception in 1984 until 31 December 1996 were inspected and those relating to urological abnormalities were abstracted. Information about postnatal progress was often missing. Twenty-three hospitals delivering maternity services were identified and randomly allocated a code letter a-w. Data were analysed in two periods, 1984-90 and 1991-96. To quantify hospital performance an 'expected number' for each hospital was calculated from the overall incidence per 1000 births and the number of births in each hospital.
There was a clear improvement in antenatal diagnostic sensitivity for the major urological abnormalities in the second period, but there was considerable variation among hospitals in the number of cases notified; this applied particularly to antenatal renal dilatation. Two hospitals notified significantly more cases in this category than all the others. The difference in notification rates among hospitals was caused by diagnoses such as vesico-ureteric reflux (VUR), pelvi-ureteric junction obstruction and megaureter, which often produce antenatal renal dilatation. Hospitals which notified more of these cases performed more micturating cystograms and identified more children with VUR. Measurements of the fetal renal pelvis were regularly made by only seven hospitals; one of these had difficulties with postnatal follow-up. There was evidence that moderate degrees of antenatal renal dilatation (4-10 mm) were associated with VUR; 8.5% of the children in whom VUR was diagnosed had fetal renal dilatation of this order.
Antenatal renal dilatation and its significance are either not being recognized or not appreciated in some hospitals. The high incidence of VUR in cases with moderate antenatal renal dilatation indicates that children with this condition may be escaping diagnosis.
BJU International 11/1999; 84(6):693-700. · 3.13 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The dynamics of perinatal mortality rates (PNMR) and causes of death in twin pregnancies over 13 years in the Northern Region of the National Health Service in England is described. All twin perinatal deaths occurring between 1982-1994 were identified from the Northern Region Perinatal Mortality Survey. The twinning rate increased from 9.9 per 1000 maternities in 1982 to 12.0 in 1994. There was a total of 10,734 twin pregnancies and of these 421 resulted in 530 perinatal deaths. The perinatal mortality rate in twins significantly decreased over time (1982-87, 55.4 per 1000; 1988-94, 44.4 per 1000; P = 0.01). The PNMR was significantly higher for twins from like-sexed than from unlike-sexed pairs (53.5 and 34.4 per 1000 respectively, P < 0.001). Despite no improvement in birthweight distribution in the twin population, birthweight-specific perinatal mortality rates for both like and unlike-sexed twins decreased for each birthweight category in 1988-94 compared with 1982-87. Twins with very low birthweight (< 1500 g) comprised 69%, and preterm twins (< 37 completed weeks of gestation) 74.9% of all twin perinatal deaths. The major immediate cause of early neonatal death was pulmonary immaturity (63%); antepartum anoxia caused 76.9% of antenatal deaths. Unexplained preterm labour and intrauterine death were the leading obstetric factors underlying death in twins. Despite a decrease over the 13 years, the perinatal mortality rate in twins in the Northern Region remains high. Continued monitoring of trends in twinning and mortality rates is needed to inform health care planning.
[Show abstract][Hide abstract] ABSTRACT: The dynamics of perinatal mortality rates (PNMR) and causes of death in twinpregnancies over 13 years in the Northern Region of the National Health Servicein England is described. All twin perinatal deaths occurring between1982-1994 were identified from the Northern Region Perinatal MortalitySurvey. The twinning rate increased from 9.9 per 1000 maternities in 1982 to 12.0in 1994. There was a total of 10734 twin pregnancies and of these 421 resulted in530 perinatal deaths. The perinatal mortality rate in twins significantly decreasedover time (1982-87, 55.4 per 1000; 1988-94, 44.4 per 1000; P =0.01). The PNMR was significantly higher for twins from like-sexed than fromunlike-sexed pairs (53.5 and 34.4 per 1000 respectively, P < 0.001).Despite no improvement in birthweight distribution in the twin population,birthweight-specific perinatal mortality rates for both like and unlike-sexed twins decreased for each birthweight category in 1988-94 compared with1982-87. Twins with very low birthweight ( < 1500 g) comprised 69%, andpreterm twins ( < 37 completed weeks of gestation) 74.9% of all twin perinataldeaths. The major immediate cause of early neonatal death was pulmonary immaturity(63%); antepartum anoxia caused 76.9% of antenatal deaths. Unexplained pretermlabour and intrauterine death were the leading obstetric factors underlying death intwins. Despite a decrease over the 13 years, the perinatal mortality rate in twinsin the Northern Region remains high. Continued monitoring of trends in twinning andmortality rates is needed to inform health care planning.
[Show abstract][Hide abstract] ABSTRACT: Editor-Kelvin H Tan and colleagues' paper analysing the incidence of congenital abdominal wall defects highlights the need for adequate antenatal and postnatal data collection nationwide.1 The authors retrospectively analysed abdominal wall defects coded according to the ninth revision of the International Classification of Diseases, using data from the Office of Population Censuses and Surveys (now the Office for National Statistics). It is not possible to differentiate between gastroschisis and exomphalos with these codes, and reanalysis of the original forms was therefore necessary. Records of the incidence of such defects may be influenced by differing regional uptakes of abortion services and variations in methods and skill in antenatal diagnosis and postnatal management. There are too many variables in the study to draw firm conclusions. In our unit, with 17 000 deliveries over the past seven years, there were seven cases of exomphalos and four of gastroschisis. Six fetuses with exomphalos and one with gastroschisis were terminated after detailed counselling and karyotyping. These diagnoses are now made at between 11 and 14 weeks' gestation as part of the nuchal thickening programme. Earlier diagnosis tends to influence the decision to terminate and emphasises the need for meticulous record keeping. Data from the Office for National Statistics are unsuitable for epidemiological research because of underreporting, but such research is vital to support current trends in primary health care. In the same issue of the BMJ a news item reports on the Gulf war syndrome2; the possibility of associated fetal anomalies cannot be analysed because of inadequate data. A further news article reports a possible connection between fluoxetine and minor birth defects.3 Do we have to have another disaster of thalidomide proportions before a national register of congenital malformations is instigated? One of us (JS) wrote her master of science dissertation on the provision of local registers of congenital malformations in England and Wales. In 1995 there were nine such registers, situated in different health regions and with varying catchment areas. Two registers related to regional referral centres, one covered roughly half a region, and the six others served entire regions (old boundaries). Figure 1 shows the areas covered. Several centres stated that their funds were precarious, and most relied on voluntary notification from motivated maternity units.
BMJ Clinical Research 02/1997; 314(7077):371-371. · 14.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: One hundred and twenty abdominal wall defects were notified to the Northern Region Fetal Abnormality Survey in the five years 1988 to 1992. Gastroschisis occurred in 56, exomphalos in 43, amnion rupture in 11, ectopia vesicae in seven and ectopia cordis in three. Ultrasound failed to identify gastroschisis in 14 and incorrectly diagnosed exomphalos in eight. There was no associated chromosome abnormality and the survival rate, excluding first trimester loss, was 87%. Ultrasound failed to identify exomphalos in ten and incorrectly diagnosed gastroschisis in two. Another structural abnormality was present in 40% and a chromosome anomaly in 28%. Excluding spontaneous first trimester loss, the survival rate was 34%. Delivery of babies away from the regional paediatric surgical centre did not adversely affect the outcome in gastroschisis or exomphalos although closure was delayed, on average, by 2 h. There was one survivor of 11 fetuses with amnion rupture sequence. Six of the seven babies with ectopia vesicae and two of the three with ectopia cordis survived.
[Show abstract][Hide abstract] ABSTRACT: This study analyses 7 years of data relating to congenital diaphragmatic herniation in the Northern Region. Ninety-nine confirmed cases were notified to the Northern Region Fetal Abnormality Survey between 1985 and 1991, which is an incidence of 0.35 per 1000 births. A specific diagnosis of CDH was made by antenatal ultrasound in 21 fetuses. The rate of detection improved from 6% to 41% but this had no impact on survival; severe pulmonary hypoplasia was found in the majority dying in the first 48 h. Another structural abnormality occurred in 29% and was the primary antenatal scan diagnosis in 11 fetuses. No other reliable indicator of outcome was identified, including the gestation when detected. The incidence of chromosomal abnormality was 5% and Fryns' syndrome 4%.
[Show abstract][Hide abstract] ABSTRACT: From 1 January 1985 to 31 December 1990, the Northern Region Fetal Abnormality Survey received 736 notifications of fetuses with suspected urological abnormalities; a prevalence of three per 1000 births. There was a male:female ratio of 2:1, the ratio was higher in obstructive than in intrinsic renal parenchymal lesions. Overall diagnostic sensitivity was 68.9% and positive predictive value 50.8%. Hydronephrosis was the most frequent antenatal diagnosis (421 cases, 57.2%): 233 (55.3%) of these were found to be normal postnatally. There were 52 other false positive diagnoses. Of 113 babies with confirmed hydronephrosis antenatal diagnosis was correct in 97, sensitivity 85.8%, specificity 48.1%; 1.8% of these had chromosome defects. In 33 cases of bilateral renal agenesis antenatal diagnosis was correct or potentially correct in 24, sensitivity 72.7%, specificity 98.9%. Only six of 26 babies with posterior urethral valves were suspected, sensitivity 23%, specificity 98.7%. Mortality rate in 91 babies with unsuspected abnormalities was 39.6%: overall mortality was 24.2%. Unsuspected abnormalities occurred more frequently when mothers were not scanned after the 16th week of pregnancy.
Archives of Disease in Childhood 02/1993; 68(1 Spec No):22-6. · 2.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The ability of routine obstetric ultrasound to detect and accurately describe fetuses with anterior abdominal wall defects has been examined in an unselected population using data from a regional abnormality survey. Examination between 16 and 22 weeks gestation detected 60% of defects with a false positive rate of 5.3%. Fetuses with gastroschisis were incorrectly assigned as exomphalos in 14.7% of cases recognized before 22 weeks gestation. The diagnosis, including description of associated detectable anomalies, was completely accurate in 71.6% of cases. Some of the problems of diagnostic accuracy need to be considered when counselling couples with a fetal anomaly. Cross-referral between obstetric ultrasound units should be encouraged to improve diagnostic accuracy. These results form the basis for audit of obstetric ultrasound in the diagnosis of fetal abnormality within a geographically defined population.
British Journal of Radiology 05/1992; 65(772):298-301. · 1.53 Impact Factor