Prenatal diagnosis of chromosomal aberrations by chromosomal microarray analysis and pregnancy outcomes of fetuses with polyhydramnios

Figures & data

Figure 1. Flowchart of CMA in fetuses with polyhydramnios. Abbreviations: CMA, chromosome microarray; QF-PCR, quantitative fluorescent polymerase chain reaction; FISH, fluorescence in situ hybridization; P/LP CNV, pathogenic/likely pathogenic copy number variants; TOP, termination of pregnancy.

Table 1. Comparison of detection rates of chromosomal anomalies between isolated and non-isolated polyhydramnios.

Polyhydramnios	Case number	Aneuploidy	pCNV (n (%))		Total pathogenic findings (n (%))	p
		(n (%))	>10 Mb	<10 Mb
Isolated	261	4 (1.5%)	0	2 (0.8%)	6 (2.3%)
Non-isolated	339	17 (5.0%)	4 (1.2%)	8 (2.4%)	29 (8.6%)	0.0243^†*/0.0288^‡*
Soft markers	88	4 (4.5%)	0	0	4 (4.5%)	0.2790^§
Structural anomalies	251	13 (5.2%)	4 (1.6%)	8 (3.2%)	25 (10.0%)	0.0003^§*
Total	600	21 (3.5%)	4 (0.7%)	10 (1.7%)	35 (5.8%)

Abbreviations: pCNV, pathogenic copy number variants.

*p < 0.05 was considered to be statistically significant.

^†Aneuploidy detection rate in the non-isolated group compared with that in the isolated group.

^‡pCNV detection rate in the non-isolated group compared with that in the isolated group.

^§Total chromosome aberrations in the corresponding group compared with those in isolated polyhydramnios.

Table 2. Comparison of pregnancy outcomes between fetuses with isolated and non-isolated polyhydramnios with CMA negative results.

Pregnancy outcomes	Isolated (n, %)	Non-isolated (n, %)		p^†
		Soft marker	Structural anomalies
Live healthy	237 (95.6)	75 (94.9)	108 (49.8)	<0.0001*
TOP	2 (0.8)	0	38 (17.5)	<0.0001*
Neonatal/childhood death	1 (0.4)	1 (1.3)	15 (6.9)	0.0001*
Intrauterine death	3 (1.2)	0	3 (1.4)	>0.9999
Neurodevelopmental disorders	4 (1.6)	1 (1.3)	4 (1.8)	>0.9999
Non-neurodevelopmental disorders
No surgery	0	2 (2.5)	22 (10.1)	<0.0001*
Surgery	1 (0.4)	0	27 (12.4)	<0.0001*
Total number of follow-up cases	248	79	217
Loss to follow-up	5	4	4
Total	253	83	221

Abbreviations: TOP, termination of pregnancy.

*p < 0.05 was considered to be statistically significant.

^†Structural anomaly group vs. isolated group.

Table 3. Poor prognostic outcomes in fetuses with normal CMA results in isolated group.

Case	Prenatal ultrasound finding	Pregnant outcomes	Postnatal disease
1	Polyhydramnios	Mortality	CHARGE syndrome (CHD7 c.2959C > T)
2	Polyhydramnios	Surgery	Total anomalous pulmonary venous connection
3	Polyhydramnios	Abnormal nerve reflex
4	Polyhydramnios	Developmental retardation
5	Polyhydramnios	Cognitive impairment
6	Polyhydramnios	Global development delay

Abbreviations: NA, not available; CMA, chromosome microarray analysis; WES, whole exome sequencing.

Data availability statement

Data is available on request from the authors.