The value of England and Wales congenital malformation notification scheme data for epidemiology: male genital tract malformations.

Abstract

SUMMARY Data from the England and Wales national congenital malformation notification scheme were examined for associations of male genital tract malformations. For some of the malformations comparison ofnotification rates with the literature suggested gross undernotification. There was also evidence suggesting bias: examination of the relationships of the malformations to birth weight, maternal parity, and maternal age at delivery showed some highly significant trends in risk, most of which were at variance with findings in the literature, and several potential mechanisms for bias could be adduced. Direct investigation is needed, for this and other similar data sets, of the extent and mechanisms of biased undernotification. Wales data set and, potentially, other similar data sets elsewhere. The other study malformations (epispadias and hydrocoele) do not appear to have received previous epidemiological study.

Congenital anterior abdominal wall defects in England and Wales 1987-93: retrospective analysis of OPCS data

“…Series DH3 publications give figures on the number of total births by area of residence and maternal age17, and these figures show an increase from south to north in the United Kingdom in the number of women under 20 giving birth (table 5). This finding may be partly responsible for the increased incidence of gastroschisis in the north of England, although both gastroschisis and exomphalos show the same regional, but not age specific, trend 18 19 20 21…”

“…39 These include the under-notification and misclassification of major congenital malformations, underascertainment of additional malformations, and overnotification of trivial malformations 18 19. Congenital anterior abdominal wall defects should be readily apparent and diagnosed at birth and therefore should be reliably ascertained by the OPCS system, in contrast with conditions which are “internal” malformations 19 20 21. Data from the west Midlands, however, indicate that 65 babies with gastroschisis were operated on by the paediatric surgical unit between 1987 and 1993, whereas 46 cases were reported to OPCS, indicating undernotification (V Upadhyay et al, British Paediatric Association, York, 1995).…”

Evidence of an environmental contribution to the aetiology of cryptorchidism and hypospadias?

“…Additionally, evidence suggests that there is geographical variation in the birth prevalence of these anomalies. Reported estimates of birth prevalence vary markedly [2,[6][7][8]. In the Northern Region of England, during the period 1993-2000, the birth prevalence of hypospadias and cryptorchidism was 3.1 and 7.6 per 1,000 males live births, respectively [5].…”

Prevalence of hypospadias in the same geographic region as ascertained by three different registries

“…NCAS's low ascertainment is likely to be mainly due to a broadened exclusion criteria now excluding glandular (or so‐called mild) hypospadias (since 1990), causing an up to 75% drop, from 2.44 in 1989, to 1.34 (1990), 0.89 (1992), and 0.63 (by 1995) (Swerdlow and Melzer, 1988). However, the exclusion of mild cases does not appear warranted because mild and severe hypospadias may well share the same etiology (Baskin, 2000) and all three require surgery.…”