Fetal fraction in maternal plasma cell-free DNA at 11-13 weeks' gestation: relation to maternal and fetal characteristics.
Ultrasound Obstet Gynecol
; 41(1): 26-32, 2013 Jan.
Article
em En
| MEDLINE
| ID: mdl-23108725
ABSTRACT
OBJECTIVE:
To examine the possible effects of maternal and fetal characteristics on the fetal fraction in maternal plasma cell-free (cf) DNA at 11-13 weeks' gestation and estimate the proportion of pregnancies at high risk of non-invasive prenatal testing (NIPT) failure because the fetal fraction is less than 4%.METHODS:
In 1949 singleton pregnancies at 11-13 weeks' gestation cf-DNA was extracted from maternal plasma. Chromosome-selective sequencing of non-polymorphic and polymorphic loci, where fetal alleles differ from maternal alleles, was used to determine the proportion of cf-DNA that was of fetal origin. Multivariable regression analysis was used to determine significant predictors of the fetal fraction among maternal and fetal characteristics.RESULTS:
The fetal fraction decreased with increased maternal weight, it was lower in women of Afro-Caribbean origin than in Caucasians and increased with fetal crown-rump length, serum pregnancy-associated plasma protein-A, serum free ß-human chorionic gonadotropin, smoking and trisomy 21 karyotype. The median fetal fraction was 10.0% (interquartile range, 7.8-13.0%) and this decreased with maternal weight from 11.7% at 60 kg to 3.9% at 160 kg. The estimated proportion with fetal fraction below 4% increased with maternal weight from 0.7% at 60 kg to 7.1% at 100 kg and 51.1% at 160 kg.CONCLUSIONS:
Fetal fraction in maternal plasma cf-DNA is affected by maternal and fetal characteristics.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Primeiro Trimestre da Gravidez
/
DNA
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Alelos
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Sangue Fetal
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Testes para Triagem do Soro Materno
Tipo de estudo:
Etiology_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adult
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Female
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Humans
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Male
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Pregnancy
Idioma:
En
Revista:
Ultrasound Obstet Gynecol
Ano de publicação:
2013
Tipo de documento:
Article