Screening for Down syndrome.
D000649:Amniocentesis / Q000009:adverse effects*; D004314:Down Syndrome / Q000517:prevention & control*; D005260:Female; D006801:Humans; D008403:Mass Screening; D008423:Maternal Age; D011247:Pregnancy; D000509:alpha-Fetoproteins / Q000032:analysis
D000509:alpha-Fetoproteins