差分
編集の要約なし
|}
* https://www.ncbi.nlm.nih.gov/pubmed/11943789
* http://journals.sagepub.com/doi/pdf/10.1136/jms.9.1.2
* http://downsyndrome.about.com/od/diagnosingdownsyndrome/a/Matagechart.htm
* https://commons.wikimedia.org/wiki/File:Down_Syndrome_Risk_by_Maternal_Age-semilog.svg