Stolwijk A M, Jongbloet P H, Zielhuis G A, Gabreëls F J
Department of Medical Informatics, Epidemiology and Statistics, University of Nijmegen, The Netherlands.
J Epidemiol Community Health. 1997 Aug;51(4):350-3. doi: 10.1136/jech.51.4.350.
Many studies on seasonality in Down syndrome (DS) have been performed and have come to different conclusions. It is suggested that seasonal variation in hormone production by the hypothalamus-pituitary-ovarian axis just before ovulation leads to seasonality in conception rates of DS. This study aimed to determine whether there is seasonal variation in the prevalence of DS at birth as a proxy for seasonality in DS at conception.
All the English and Dutch articles on this topic were reviewed. Articles published between 1966 and January 1996 were traced by Medline, and by the reference lists.
Twenty articles met the criteria for inclusion. Although seven of these studies reported seasonality in DS prevalence, no consistent seasonal pattern was found in DS at birth in these studies, or in the remaining studies. A seasonal pattern could not have been masked by the effects of maternal age, induced abortions, shortened gestation, or misclassification of DS.
Seasonality in the prevalence of DS at birth does not exist. Evidence did not support the suggestion that DS occurrence is related to seasonality in hormone production.
已开展了许多关于唐氏综合征（DS）季节性的研究，且得出了不同结论。有观点认为，排卵前下丘脑 - 垂体 - 卵巢轴激素分泌的季节性变化导致了唐氏综合征受孕率的季节性变化。本研究旨在确定出生时唐氏综合征患病率是否存在季节性变化，以此作为唐氏综合征受孕季节性的替代指标。
对关于该主题的所有英文和荷兰文文章进行了综述。通过医学文献数据库（Medline）以及参考文献列表，检索了1966年至1996年1月期间发表的文章。
20篇文章符合纳入标准。尽管其中7项研究报告了唐氏综合征患病率的季节性，但在这些研究中，或在其余研究中，均未发现出生时唐氏综合征存在一致的季节性模式。唐氏综合征患病率的季节性模式不可能被母亲年龄、人工流产、孕周缩短或唐氏综合征的错误分类所掩盖。
出生时唐氏综合征患病率不存在季节性。证据不支持唐氏综合征的发生与激素分泌季节性有关这一观点。
