Trisomies 18 and 13: trends in prevalence and prenatal diagnosis - population based study.

OBJECTIVE: The objective of this study was to determine trends in prenatal detection and current estimates of prevalence for trisomies 18 (T18) and 13 (T13) and their implications for screening policy. METHODS: We conducted a cohort study from a population-based regional anomaly register covering 995 003 births (1995-2009). RESULTS: There were 786 affected cases. Total prevalence of T18 increased from 3.95 in 1995-1999 to 6.94 per 10 000 births in 2005-2009 (annual trend χ(2) = 25.99, p < 0.001) and live birth prevalence, when adjusted for in utero attrition, increased from 1.47 to 2.30 per 10 000 births over the same time (annual trend χ(2) = 6.36, p = 0.01). For T18 and T13 combined, the proportion of cases diagnosed by prenatal karyotype or suspected by ultrasound increased from 85.1% (165/194) in 1995-1999 to 95.2% (299/314) in 2005-2009 (p < 0.001). In 2005-2009, 50.3% of prenatal cytogenetic diagnoses for T18 and 38.5% of T13 were made after the discovery of first trimester ultrasound anomalies, and the majority, 56.4% (185/328), of affected pregnancies were karyotyped or had ended before 18 weeks. CONCLUSION: T18 is increasing in prevalence because of maternal age and earlier surveillance. Prenatal diagnosis occurs mostly in the first trimester, without the intrinsic structures of a formal screening programme. These findings support the extension of first trimester combined screening to include T18 and T13.

Congenital lower urinary tract obstruction: a population-based epidemiological study.

OBJECTIVE: To determine the prevalence and outcome of lower urinary tract obstruction (LUTO), including the sensitivity of antenatal diagnosis. DESIGN: A retrospective population-based study. SETTING: Regional population-based congenital anomalies register (WMCAR). POPULATION: Fetuses affected by LUTO delivered between 1995 and 2007 to women resident in the West Midlands. METHODS: Cases were selected from the WMCAR using codes and keyword terms from the International Classification of Diseases, tenth revision (ICD10). Diagnoses were validated using additional data sets from Regional Fetal Medicine, Perinatal Pathology and Paediatric services. MAIN OUTCOME MEASURES: Rates of prevalence, prenatal diagnosis and mortality, with trends. RESULTS: There were 284 LUTO cases in 851 419 births during the study period, representing a total prevalence of 3.34 (2.95-3.72) per 10 000 births, and this prevalence did not change significantly over time. The prevalence of LUTO was significantly higher in Black and minority ethnic groups when compared with white Europeans (OR 2.38; 95% CI 1.87-3.03), and are associated with area-based deprivation measures (P < 0.01). Of all LUTO cases, 221 (77.8%) were isolated, and the remainder were associated with other structural or chromosomal anomalies. The most common subtype was posterior urethral valves (PUVs; n = 179, 63%). In total there were 211 (74.3%) cases of isolated, non-female, singleton fetuses that fitted the referral criteria for in utero vesico-amniotic shunting, giving a prevalence of 2.48 (2.14-2.81) per 10 000 live births. Within this group, the prenatal diagnosis rate was 46.9% (99/211). CONCLUSION: This is the largest population-based study of LUTO that has been performed to date, and provides accurate estimates for prevalence. The low prevalence and relatively low rate of antenatal detection limit the number of cases amenable to prenatal surgical intervention.

Pulse oximetry as a screening test for congenital heart defects in newborn infants: a test accuracy study with evaluation of acceptability and cost-effectiveness.

BACKGROUND: Screening for congenital heart defects (CHDs) relies on antenatal ultrasound and postnatal clinical examination; however, life-threatening defects often go undetected. OBJECTIVE: To determine the accuracy, acceptability and cost-effectiveness of pulse oximetry as a screening test for CHDs in newborn infants. DESIGN: A test accuracy study determined the accuracy of pulse oximetry. Acceptability of testing to parents was evaluated through a questionnaire, and to staff through focus groups. A decision-analytic model was constructed to assess cost-effectiveness. SETTING: Six UK maternity units. PARTICIPANTS: These were 20,055 asymptomatic newborns at ≥ 35 weeks' gestation, their mothers and health-care staff. INTERVENTIONS: Pulse oximetry was performed prior to discharge from hospital and the results of this index test were compared with a composite reference standard (echocardiography, clinical follow-up and follow-up through interrogation of clinical databases). MAIN OUTCOME MEASURES: Detection of major CHDs - defined as causing death or requiring invasive intervention up to 12 months of age (subdivided into critical CHDs causing death or intervention before 28 days, and serious CHDs causing death or intervention between 1 and 12 months of age); acceptability of testing to parents and staff; and the cost-effectiveness in terms of cost per timely diagnosis. RESULTS: Fifty-three of the 20,055 babies screened had a major CHD (24 critical and 29 serious), a prevalence of 2.6 per 1000 live births. Pulse oximetry had a sensitivity of 75.0% [95% confidence interval (CI) 53.3% to 90.2%] for critical cases and 49.1% (95% CI 35.1% to 63.2%) for all major CHDs. When 23 cases were excluded, in which a CHD was already suspected following antenatal ultrasound, pulse oximetry had a sensitivity of 58.3% (95% CI 27.7% to 84.8%) for critical cases (12 babies) and 28.6% (95% CI 14.6% to 46.3%) for all major CHDs (35 babies). False-positive (FP) results occurred in 1 in 119 babies (0.84%) without major CHDs (specificity 99.2%, 95% CI 99.0% to 99.3%). However, of the 169 FPs, there were six cases of significant but not major CHDs and 40 cases of respiratory or infective illness requiring medical intervention. The prevalence of major CHDs in babies with normal pulse oximetry was 1.4 (95% CI 0.9 to 2.0) per 1000 live births, as 27 babies with major CHDs (6 critical and 21 serious) were missed. Parent and staff participants were predominantly satisfied with screening, perceiving it as an important test to detect ill babies. There was no evidence that mothers given FP results were more anxious after participating than those given true-negative results, although they were less satisfied with the test. White British/Irish mothers were more likely to participate in the study, and were less anxious and more satisfied than those of other ethnicities. The incremental cost-effectiveness ratio of pulse oximetry plus clinical examination compared with examination alone is approximately £24,900 per timely diagnosis in a population in which antenatal screening for CHDs already exists. CONCLUSIONS: Pulse oximetry is a simple, safe, feasible test that is acceptable to parents and staff and adds value to existing screening. It is likely to identify cases of critical CHDs that would otherwise go undetected. It is also likely to be cost-effective given current acceptable thresholds. The detection of other pathologies, such as significant CHDs and respiratory and infective illnesses, is an additional advantage. Other pulse oximetry techniques, such as perfusion index, may enhance detection of aortic obstructive lesions. FUNDING: The National Institute for Health Research Health Technology programme.

Termination of pregnancy for fetal anomaly: a population-based study 1995 to 2004.

Terminations of pregnancy for fetal anomaly (TOPFAs) were analysed over a 10-year period from a population-based congenital anomaly register covering 646,342 births. A total of 3189 cases of TOPFA were identified, prevalence of 49.3 per 10,000 registerable births. The rate of TOPFA at all gestations and at less than 16 weeks increased significantly. There were 102 cases of liveborn TOPFAs (3.2%). The proportion of liveborn TOPFAs after 22 weeks of gestation decreased significantly but below 22 weeks remains unchanged. TOPFA is increasing in frequency, occurring earlier in pregnancy. Live birth is a possible important outcome.

Reversal of female sterilisation experience in a district general hospital.

Forty-five women who had microsurgical reversal of tubal sterilisation in New Cross Hospital Wolverhampton, between January 1986 and December 1992, were analysed to determine the success rate and the influencing factors. These women were followed-up until September 1994. More than 80% of the women were sterilised before the age of 30, and more than 80% sought reversal because of change of relationship. The overall pregnancy rate was 57.8% (intrauterine 51.1%, ectopic 6.7%). There were 17 (37.8%) live births. Intrauterine pregnancy rate was 100% (6/6) for the reversal of previous Filshie clip sterilisation, 50% (17/34) for previous Falope ring application and 0% (0/5) for previous Pomeroy method (P < 0.001). Analysis according to the site of anastomosis showed that the isthmic-isthmic anastomosis had an intrauterine pregnancy rate of 87.5% (7/8), isthmic-ampullary: 48.4% (15/31) and ampullary-ampullary: 16.7% (1/6), (P < 0.02). Sterilisation-reversal interval had no significant influence on the intrauterine pregnancy rate.

Nimodipine levels in breast milk.

Nimodipine is an established drug in the treatment of symptomatic subarachnoid haemorrhage. However no data exist as to whether the drug has been detected in breast milk. This paper reports on a lactating patient who was commenced on nimodipine for a symptomatic arterial spasm after aneurysm surgery. Assays demonstrated that nimodipine was detected in the breast milk in relatively similar concentrations to plasma.

Comparison of ulnar and radial arterial blood-flow at the wrist.

Historical descriptions of the ulnar artery as the dominant vessel to the hand appear to be inconsistent with clinical experience. Anatomical dissections and radionucleotide flow studies of the ulnar and radial arteries at the wrist were performed. These failed to demonstrate any difference between the anatomical dimensions of these vessels, but the radial artery was shown to have a statistically greater blood flow compared to the ulnar artery. This finding suggests that, contrary to popular opinion, the radial artery is the dominant vessel to the hand.