Prevalence of common aneuploidy in twin pregnancies.
J Hum Genet
; 67(5): 261-265, 2022 May.
Article
in En
| MEDLINE
| ID: mdl-34974528
ABSTRACT
The incidence of chromosomal abnormalities in twin pregnancies is not well-studied. In this retrospective study, we investigated the frequency of chromosomal abnormalities in twin pregnancies and compared the incidence of chromosomal abnormalities in dichorionic diamniotic (DD) and monochorionic diamniotic (MD) twins. We used data from 57 clinical facilities across Japan. Twin pregnancies of more than 12 weeks of gestation managed between January 2016 and December 2018 were included in the study. A total of 2899 and 1908 cases of DD and MD twins, respectively, were reported, and the incidence of chromosomal abnormalities in one or both fetuses was 0.9% (25/2899) and 0.2% (4/1908) in each group (p = 0.004). In this study, the most common chromosomal abnormality was trisomy 21 (51.7% [15/29]), followed by trisomy 18 (13.8% [4/29]) and trisomy 13 (6.9% [2/29]). The incidence of trisomy 21 in MD twins was lower than that in DD twins (0.05% vs. 0.5%, p = 0.007). Trisomy 21 was less common in MD twins, even when compared with the expected incidence in singletons (0.05% vs. 0.3%, RR 0.15 [95% CI 0.04-0.68]). The risk of chromosomal abnormality decreases in twin pregnancies, especially in MD twins.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Down Syndrome
/
Chromosome Disorders
Type of study:
Observational_studies
/
Prevalence_studies
/
Risk_factors_studies
Limits:
Female
/
Humans
/
Pregnancy
Language:
En
Journal:
J Hum Genet
Journal subject:
GENETICA MEDICA
Year:
2022
Document type:
Article
Affiliation country:
Japón