Copy number variations and pregnancy outcomes of fetuses with mild to moderate isolated ventriculomegaly
10.3760/cma.j.cn113903-20231130-00354
- VernacularTitle:轻中度孤立性侧脑室增宽胎儿的拷贝数变异及妊娠结局
- Author:
Qingmei SHEN
1
;
Xiaoqing WU
;
Danhua GUO
;
Bin LIANG
;
Meiying WANG
;
Lin ZHENG
;
Hua CAO
;
Liangpu XU
Author Information
1. 福建省妇幼保健院（福建医科大学妇儿临床学院）医学遗传诊疗中心（福建省产前诊断与出生缺陷重点实验室），福州 350001
- Keywords:
Fetal ventriculomegaly;
Prenatal diagnosis;
Chromosomal microarray analysis;
Copy number variations;
Prognosis
- From:
Chinese Journal of Perinatal Medicine
2024;27(10):829-835
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore chromosomal copy number variations (CNVs) and pregnancy outcomes in fetuses with mild to moderate isolated ventriculomegaly (IVM), but without other indications for invasive prenatal diagnosis.Methods:A retrospective analysis was conducted on clinical data of 215 singleton pregnancies with mild to moderate IVM (lateral ventricular width≥10-<15 mm) who underwent chromosomal microarray analysis (CMA), not indicated by advanced age, high risk in serum screening or abnormal history of pregnancy, at the Fujian Maternity and Child Health Hospital between June 2016 and March 2023. The 215 fetuses were grouped into mild ( n=167) and moderate ( n=48) IVM;unilateral ( n=142) and bilateral ( n=73) IVM; first diagnosis of IVM before 28 weeks ( n=138) and thereafter ( n=77). Anomalies other than IVM were excluded via three-dimensional color Doppler ultrasound examination between 22 and 26 weeks of gestation. Out of these cases, 129 were confirmed by fetal cranial MRI, 191 underwent chromosomal karyotype analysis, and 202 cases received cytomegalovirus DNA quantification test for amniotic fluid. The detection rates of pathogenic CNVs in various groups were compared using Fisher's exact test. Results:Among the 215 fetuses, 11 cases (5.1%) of chromosomal abnormalities were detected through CMA, including one trisomy 21, five pathogenic CNVs, and five CNVs of uncertain clinical significance. Within the pathogenic CNVs, there were two de novo mutations with 16p11.2 microdeletion and one de novo mutation with 16p11.2 microduplication, while one 16p11.2 microduplication and one Xp22.31 microdeletion were inherited maternally. Of the CNVs of uncertain significance, there were two 16p13.11 microduplications, each inherited from a different parent, one paternally and one maternally; meanwhile, family validation was refused in the other three cases with 3p22.1 microdeletion, 3p26.3 microdeletion, and 9q21.33q22.31 microduplication. The detection rate of pathogenic CNVs in the moderate IVM group was higher than that in the mild IVM group [6.3% (3/48) vs. 1.2% (2/167)], but the difference was not statistically significant ( P=0.083). Similarly, no significant difference was found in the detection rate of pathogenic CNVs when comparing the unilateral IVM group [2.1% (3/142)] with the bilateral IVM group [2.7% (2/73)], nor between the group diagnosed with VM before 28 weeks gestation [2.2% (3/138)] and that diagnosed ≥28 weeks [2.6% (2/77)] (both P>0.05). After the exclusion of fetuses with chromosomal pathogenic abnormalities ( n=11), cytomegalovirus infection( n=1), and additional ultrasound anomalies ( n=7), and several cases with missing data intrauterine outcomes were followed up in 169 IVM fetuses, including 104 (61.5%) improved, 60 (35.5%) unchanged, and five (3.0%) progressed. Follow-ups were successful for 194 women, of which eight pregnancies were terminated (including one trisomy 21, four pathogenic CNVs, one fetal cytomegalovirus infection, and two progressed to severe IVM). Among the 186 newborns, one was diagnosed with X-linked ichthyosis, and one child who progressed to severe IVM before born was followed until 20 months of age without notable phenotypic abnormalities. The rest 184 babies, including those with CNVs of uncertain clinical significance, exhibited no developmental abnormalities during follow-up between the ages of three months and six years. Conclusions:For those fetuses with isolated mild to moderate IVM, but without indications for prenatal diagnosis such as advanced maternal age, high risk in serum screening or abnormal history of pregnancy, remain having the risk for chromosomal aberrations, and 16p11.2 microdeletion/microduplication might be a frequent CNV associated with this condition. Aside from those with pathogenic chromosomal aberrations, fetal cytomegalovirus infection, or progressive enlargement of the lateral ventricles, most fetuses with isolated mild to moderate IVM have a good prognosis.
