caa a22 4500 388116048 CHVBK 20180307125407.0 cr unu---uuuuu 161130e199907 xx s 000 0 eng 10.1017/S1047951100005205 doi S1047951100005205 pii (NATIONALLICENCE)cambridge-10.1017/S1047951100005205 Grech Victor Paediatric Department, St Luke's Hospital, Guardamangia, Malta Seasonality in live births with congenital heart disease in Malta [Elektronische Daten] [Victor Grech] This study was carried out to analyse seasonal variations in live births with congenital heart disease in the overall population of Malta. Included were all patients diagnosed as having congenital heart disease by echocardiography, cardiac catheterization, surgery or post mortem, by 1 year of age, and who were born between in Malta between 1990 and 1994. Results were analysed by χ2 and by Edwards' cyclic method. There were 231 cases of live born congenital heart disease, which were divided into 114 cases not requiring intervention and 117 cases requiring intervention. Although the overall prevalence of congenital heart disease did not demonstrate any seasonal variation, the lesions requiring intervention showed a significant peak in September by Edwards' method (p = 0.03), which was enhanced by seasonal analysis (p = 0.003). These results were confirmed by conventional χ2 and χ2 for trend. The lesions not requiring intervention, which were comprised almost entirely (96%) of mild pulmonary stenosis and small ventricular septal defects, failed to show any seasonal trend. The literature regarding such seasonal trends in these malformations and statistical analysis of seasonality of congenital heart disease are reviewed. An environmental factor such as a maternal viral infection or treatment of such infections during the first trimester of pregnancy from November to January may precipitate congenital heart disease in predisposed Maltese foetuses. Copyright © Cambridge University Press 1999 Heart defects nationallicence congenital epidemiology nationallicence congenital aetiology nationallicence congenital season nationallicence Cardiology in the Young Cambridge University Press 9/4(1999-07), 396-401 1047-9511 9:4<396 1999 9 CTY https://doi.org/10.1017/S1047951100005205 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S1047951100005205 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Grech Victor Paediatric Department, St Luke's Hospital, Guardamangia, Malta NATIONALLICENCE 773 0- Cardiology in the Young Cambridge University Press 9/4(1999-07), 396-401 1047-9511 9:4<396 1999 9 CTY CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge