title: DOWN'S SYNDROME AT YOUNG MATERNAL AGES: CHROMOSOMAL AND FAMILY STUDIES.
mesh_terms: D002875:Chromosomes; D004314:Down Syndrome; D005260:Female; D005826:Genetics, Medical; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007620:Karyometry; D008423:Maternal Age; D011247:Pregnancy; D013223:Statistics as Topic; D014314:Trisomy
keywords: CHROMOSOMES; GENETICS, HUMAN; INFANT, NEWBORN; KARYOMETRY; MONGOLISM; PREGNANCY; STATISTICS; TRISOMY