Biomaterial Database

Maternal serum alpha-fetoprotein and fetal trisomy-21 in women 35 years and older: implications for alpha-fetoprotein screening programs. 1987

E R Ashwood, and E Cheng, and D A Luthy

A retrospective study of 3,411 women who underwent midtrimester amniocentesis for fetal chromosome analysis between June 1979 and August 1984 was performed to evaluate an association between low maternal serum alpha-fetoprotein (AFP) concentrations and Down syndrome (DS) pregnancies. A total of 71 pregnancies was found with abnormal fetal chromosomes; of these, 26 cases were trisomy-21 and 10 cases were trisomy-18. The maternal serum AFP in women with DS fetuses was relatively lower than levels in women with fetuses that had normal chromosomes. In addition, the AFP concentrations in amniotic fluid were decreased in cases involving DS fetuses. We have estimated the risks for DS pregnancy at all maternal ages and most serum AFP concentrations. Using these calculations, genetic counselors will be able to provide more accurate risk estimates for trisomy-21 following maternal serum AFP testing.

UI	MeSH Term	Description	Entries
D008423	Maternal Age	The age of the mother in PREGNANCY.	Age, Maternal,Ages, Maternal,Maternal Ages
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011296	Prenatal Diagnosis	Determination of the nature of a pathological condition or disease in the postimplantation EMBRYO; FETUS; or pregnant female before birth.	Diagnosis, Prenatal,Fetal Diagnosis,Fetal Imaging,Fetal Screening,Intrauterine Diagnosis,Antenatal Diagnosis,Antenatal Screening,Diagnosis, Antenatal,Diagnosis, Intrauterine,Prenatal Screening,Antenatal Diagnoses,Antenatal Screenings,Diagnosis, Fetal,Fetal Diagnoses,Fetal Imagings,Fetal Screenings,Imaging, Fetal,Intrauterine Diagnoses,Prenatal Diagnoses,Prenatal Screenings,Screening, Antenatal,Screening, Fetal,Screening, Prenatal
D002887	Chromosomes, Human, Pair 18	A specific pair of GROUP E CHROMOSOMES of the human chromosome classification.	Chromosome 18
D004314	Down Syndrome	A chromosome disorder associated either with an extra CHROMOSOME 21 or an effective TRISOMY for chromosome 21. Clinical manifestations include HYPOTONIA, short stature, BRACHYCEPHALY, upslanting palpebral fissures, epicanthus, Brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, single transverse palmar crease, and moderate to severe INTELLECTUAL DISABILITY. Cardiac and gastrointestinal malformations, a marked increase in the incidence of LEUKEMIA, and the early onset of ALZHEIMER DISEASE are also associated with this condition. Pathologic features include the development of NEUROFIBRILLARY TANGLES in neurons and the deposition of AMYLOID BETA-PROTEIN, similar to the pathology of ALZHEIMER DISEASE. (Menkes, Textbook of Child Neurology, 5th ed, p213)	Mongolism,Trisomy 21,47,XX,+21,47,XY,+21,Down Syndrome, Partial Trisomy 21,Down's Syndrome,Partial Trisomy 21 Down Syndrome,Trisomy 21, Meiotic Nondisjunction,Trisomy 21, Mitotic Nondisjunction,Trisomy G,Downs Syndrome,Syndrome, Down,Syndrome, Down's
D005260	Female		Females
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D000509	alpha-Fetoproteins	The first alpha-globulins to appear in mammalian sera during FETAL DEVELOPMENT and the dominant serum proteins in early embryonic life.	alpha-Fetoprotein,alpha Fetoprotein,alpha Fetoproteins