Influence of season on prevalence of cleft lip and palate

A review of seasonality of cleft births – The Brazil experience

“…The environmental factors which were cited as being related to seasonality and oral cleft included maternal dietary deficiencies, in particular low folic acid intake, ultra violet light exposure, use of fertilizers and pesticides in agriculture and infectious disease cycles. 13,15,17 In this study, nonparametric tests did not show a seasonal difference, considering the month of births and seasons, between healthy individuals and cleft patients (p = 0.902 and p = 0.679, respectively). It was identified only a difference in births between the groups in January, however, was not significant.…”

“…7,11 According to this model, the malformations result from factors such as genetic predisposition and exogenous factors like maternal malnutrition, low intake of folic acid, teratogens including drugs and alcohol, viruses and maternal age. 1,8,12 There are studies which evaluated a seasonal influence on the occurrence of CL/P [13][14][15][16][17][18][19] and they considered that it was reasonable to expect that orofacial clefts may show seasonal variations due to indirect factors such as maternal malnutrition and low intake of folic acid, 13,15 and other direct factors such as temperature, intensity of ultraviolet light exposure, use of fertilizers and pesticides in agriculture and infectious disease cycles.…”

Epidemiology of Ebstein anomaly: Prevalence and patterns in Texas, 1999–2005

“…Although this association has not been previously reported for Ebstein anomaly, it is believed that season of conception may be a proxy for temporal variability in pesticide use, maternal infection, air pollution, and dietary patterns, all suggested risk factors for a range of birth defects [Garry et al, 2002;Krost and Schubert, 2006;Ritz, 2009]. We also assessed year of birth as another predictor of temporal trends.…”

Registries of cleft lip/palate cases between 2004 and 2010 in Denizli, Turkey

“…Women who conceive during spring, summer, or autumn have a 2.6-fold increased risk of having a baby with a cleft in Germany but not in Northern Ireland (Krost and Schubert, 2006;Gregg et al, 2008). Isolated CL/P is genetically heterogeneous.…”