Detection of triploid, molar, and vanishing twin pregnancies by a single-nucleotide polymorphism-based noninvasive prenatal test.
Am J Obstet Gynecol
; 212(1): 79.e1-9, 2015 Jan.
Article
em En
| MEDLINE
| ID: mdl-25447960
ABSTRACT
OBJECTIVE:
We sought to determine the ability of single-nucleotide polymorphism-based noninvasive prenatal testing (NIPT) to identify triploid, unrecognized twin, and vanishing twin pregnancies. STUDYDESIGN:
The study included 30,795 consecutive reported clinical cases received for NIPT for fetal whole-chromosome aneuploidies; known multiple gestations were excluded. Cell-free DNA was isolated from maternal blood samples, amplified via 19,488-plex polymerase chain reaction, and sequenced. Sequencing results were analyzed to determine fetal chromosome copy number and to identify the presence of additional fetal haplotypes.RESULTS:
Additional fetal haplotypes, indicative of fetal triploidy, vanishing twin, or undetected twin pregnancy, were identified in 130 (0.42%) cases. Clinical confirmation (karyotype for singleton pregnancies, ultrasound for multifetal pregnancies) was available for 58.5% (76/130) of cases. Of the 76 cases with confirmation, 42.1% were vanishing twin, 48.7% were viable twin, 5.3% were diandric triploids, and 3.9% were nontriploid pregnancies that lacked evidence of co-twin demise. One pregnancy had other indications suggesting triploidy but lacked karyotype confirmation. Of the 5 vanishing twin cases with a known date of demise, 100% of losses occurred in the first trimester; up to 8 weeks elapsed between loss and detection by NIPT.CONCLUSION:
This single-nucleotide polymorphism-based NIPT successfully identified vanished twin, previously unrecognized twin, and triploid pregnancies. As vanishing twins are more likely to be aneuploid, and undetected residual cell-free DNA could bias NIPT results, the ability of this method to identify additional fetal haplotypes is expected to result in fewer false-positive calls and prevent incorrect fetal sex calls.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Diagnóstico Pré-Natal
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Mola Hidatiforme
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Polimorfismo de Nucleotídeo Único
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Triploidia
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Reabsorção do Feto
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Gravidez de Gêmeos
Tipo de estudo:
Diagnostic_studies
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Prognostic_studies
Limite:
Adolescent
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Adult
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Female
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Humans
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Middle aged
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Pregnancy
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article