What proportion of congenital abnormalities can be prevented?

OBJECTIVE--To estimate the proportion of preventable congenital abnormalities in Hungary. DESIGN--Analysis of available Hungarian data-bases and of the effectiveness of primary, secondary, and tertiary preventive methods. SETTING--Databases of ad hoc epidemiological studies and of the Hungarian congenital abnormality registry. MAIN OUTCOME MEASURES--Prevalence at birth and prevalence after prevention in 73 congenital abnormality types or groups. RESULTS--Preventive methods are available for 51 (70%) of the 73 congenital abnormality types or groups evaluated. The birth prevalence of all congenital abnormalities could be reduced from 65 to 26 per 1000; thus 39 per 1000 (60%) are preventable. Without congenital dislocation of the hip, which is unusually common in Hungary, the preventable proportion of congenital abnormalities is 52%. CONCLUSION--Many congenital abnormalities can be prevented, but as they do not represent a single pathological category there is no single strategy for their prevention.     

Case-control cytogenetic study in offspring of mothers treated with bromocriptine during early pregnancy

The distribution of modal and non-modal karyotypes was examined in mitoses of lymphocyte cultures of 31 children who had been exposed to bromocriptine in utero, and in 31 matched controls. No mosaicism was diagnosed. Furthermore, no more hypomodal cells occurred in the study group than in the control group.     

Congenital abnormalities and indicators of germinal mutations in the vicinity of an acrylonitrile producing factory.

The results of an environmental mutation and teratologic epidemiological study are presented which was performed in inhabitants living in the surrounding region of an acrylonitrile factory in Nyergesújfalu. The endpoint of the study was congenital abnormalities in 46,326 infants born to mothers living in the 30 settlements of the study region within a 25 km radius of the acrylonitrile factory between 1980 and 1996. The ascertainment of cases with congenital abnormalities was based on the dataset of the Hungarian Congenital Abnormality Registry complemented with the review of pediatric, pathology and cytogenetic records. A particular attention was paid to the indicators of germinal mutations as sentinel anomalies, Down syndrome and unidentified multiple congenital abnormalities and the indicators of teratogens as the specific pattern of multiple congenital abnormalities. Three congenital abnormalities: pectus excavatum in Tata, 1990-1992 (OR with 95%CI: 78.5, 8.4-729.6), undescended testis in Nyergesújfalu between 1980 and 1983 (8.6, 1.4-54.3) and in Esztergom, 1981-1982 (4. 2, 1.3-13.5) and clubfoot in Tata, 1980-1981 (5.5, 1.5-20.3) showed significant time-space clusters in the study region. There was a decrease in risk of undescended testis with increasing distance from the acrylonitrile factory. An unusual increase was found in the combination of oral cleft and cardiac septal defects in multimalformed babies in Tatabánya, 1990. The detailed analysis of congenital abnormalities in all settlements of a given territory may help to detect clusters of congenital abnormalities and their possible relation to the environmental hazards.     

Smoking during pregnancy and congenital limb deficiency.

OBJECTIVE--To examine genetic and environmental factors in the origin of isolated congenital limb deficiencies. DESIGN--Case-control study with questionnaire at a family interview of cases of isolated congenital limb deficiencies (six types), negative controls (matched for age, sex, and place of residence), and positive controls (cases of sentinel anomalies). SETTING--The database of the Hungarian Congenital Abnormality Registry, 1975-84, complemented by three other sources of ascertainment (1,575,904 births). SUBJECTS--537 case-control pairs; 392 positive controls. MAIN OUTCOME MEASURES--Smoking during pregnancy, congenital limb deficiencies. RESULTS--The adjusted rate of smoking during pregnancy was significantly higher in the mothers of cases of terminal transverse defect (relative odds 1.48; 95% confidence interval 0.98 to 2.23; P = 0.017). This finding supports the hypothesis of vascular disruption as a cause of congenital limb deficiency. CONCLUSIONS--Maternal smoking during pregnancy raises the relative odds for terminal transverse limb deficiencies.     

Correlation between the birth prevalence of isolated hypospadias and parental subfertility

Factors associated with the occurrence of isolated hypospadias have been studied. We previously reported a secular trend association between hypospadias occurrence and progestagen use by the Hungarian population. Further study does not support that secular trend association. The use of progestagens for the treatment of reproductive problems is a very complex issue, and there are other factors relating to male and female fertility that differentiate the hypospadias families from the controls. It appears that families with problems of subfertility are at increased risk for the occurrence of hypospadias. Our data support more recent studies, which do not demonstrate an association between the occurrence of hypospadias and the administration of progestagens in humans.     

Incidence of congenital heart disease in Hungary.

A survey was planned for establishing the point prevalence at birth of congenital heart disease and for assessing at the same time the efficacy of a screening for such anomalies. This model included: (1) exact determination of the population under survey; (2) approximately complete ascertainment of all persons in the population studied; (3) identical principles of cardiologic screening; (4) application of modern cardiologic diagnostic methods, and (5) a sample of over 2,000 persons. 23 cases of congenital heart diseases were found among 2,259 children born 1963 in a defined Hungarian territory. This means a point prevalence of 10.2+/-2.1% live births. (An additional 6 doubtful cases were not taken into account.) From the 12 cases diagnosed in vivo, 10 were detected by the screening.