J Clin Gynecol Obstet

Journal of Clinical Gynecology and Obstetrics, ISSN 1927-1271 print, 1927-128X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Gynecol Obstet and Elmer Press Inc

Journal website https://www.jcgo.org

Original Article

Volume 12, Number 1, March 2023, pages 8-14

Typical Morphological Features on Prenatal Ultrasound of Fetuses With Trisomy 13 (Patau’s Syndrome)

**Table 1.** Comparison of Characteristics Between Trisomy 13 and Normal Cases in Prenatal Screening
Characteristics	Trisomy 13 (n = 50)	Normal (n = 4,166)	P
Maternal age
Mean age	31.49 years	29.88 years	0.093
Age range	19 - 44 years	15 - 55 years
≥ 35 years old	20 (40%)	1,075 (25.8%)	0.059
< 35 years old	30 (60%)	3,091 (74.2%)
Gestational age
Mean age	16 weeks and 1 day	17 weeks and 3 days	0.091
Age range	11 weeks and 1 day - 24 weeks and 5 days	11 week and 0 day - 23 weeks 3 days
First pregnancy	23 (46%)	1,230 (29.5%)	0.062
Second pregnancy	26 (52%)	2,936 (70.5%)
Third pregnancy	1 (2%)	0 (0%)
History of pregnancy with trisomy
Trisomy 21	0 (0%)	33 (0.79%)	0.511
Trisomy 18	0 (0%)	3 (0.07%)
Trisomy 13	0 (0%)	0 (0%)
No	50 (100%)	4,130 (99.14%)
Personal history of chronic hypertension
Yes	0 (0%)	4 (0.1%)	0.82
No	50 (100%)	4,162 (99.9%)
Personal history of diabetes
Type 1	0 (0%)	1 (0.02%)	0.968
Type 2	0 (0%)	4 (0.1%)
No	50 (100%)	4,161 (99.88%)
Personal history of the systemic lupus erythematosus
Yes	0 (0%)	2 (0.05%)	0.872
No	50 (100%)	4,164 (99.95%)

Table 1. Comparison of Characteristics Between Trisomy 13 and Normal Cases in Prenatal Screening

Characteristics

Trisomy 13 (n = 50)

Normal (n = 4,166)

Maternal age

Mean age

31.49 years

29.88 years

0.093

Age range

19 - 44 years

15 - 55 years

≥ 35 years old

20 (40%)

1,075 (25.8%)

0.059

< 35 years old

30 (60%)

3,091 (74.2%)

Gestational age

Mean age

16 weeks and 1 day

17 weeks and 3 days

0.091

Age range

11 weeks and 1 day - 24 weeks and 5 days

11 week and 0 day - 23 weeks 3 days

First pregnancy

23 (46%)

1,230 (29.5%)

0.062

Second pregnancy

26 (52%)

2,936 (70.5%)

Third pregnancy

1 (2%)

0 (0%)

History of pregnancy with trisomy

Trisomy 21

0 (0%)

33 (0.79%)

0.511

Trisomy 18

0 (0%)

3 (0.07%)

Trisomy 13

0 (0%)

50 (100%)

4,130 (99.14%)

Personal history of chronic hypertension

Yes

0 (0%)

4 (0.1%)

0.82

50 (100%)

4,162 (99.9%)

Personal history of diabetes

Type 1

0 (0%)

1 (0.02%)

0.968

Type 2

0 (0%)

4 (0.1%)

50 (100%)

4,161 (99.88%)

Personal history of the systemic lupus erythematosus

Yes

0 (0%)

2 (0.05%)

0.872

50 (100%)

4,164 (99.95%)

**Table 2.** Causes Leading to Indications for Amniocentesis in Fetuses With Trisomy 13
Causes leading to amniocentesis	n
NIPT: non-invasive prenatal testing.
Cases of morphological abnormalities detected on ultrasound	41
Combined with a high-risk NIPT result for aneuploidies	2
Combined with a high-risk double test/triple test result for aneuploidies	10
Combined with maternal age ≥ 35 years old	6
Based only on abnormalities on ultrasound	23
Cases that were not detected morphological abnormalities on ultrasound	9
A high-risk NIPT result for aneuploidies	2
A high-risk double test/triple test result for aneuploidies	6
Based only on the maternal age ≥ 35 years old	1

Table 2. Causes Leading to Indications for Amniocentesis in Fetuses With Trisomy 13

Causes leading to amniocentesis

NIPT: non-invasive prenatal testing.

Cases of morphological abnormalities detected on ultrasound

Combined with a high-risk NIPT result for aneuploidies

Combined with a high-risk double test/triple test result for aneuploidies

Combined with maternal age ≥ 35 years old

Based only on abnormalities on ultrasound

Cases that were not detected morphological abnormalities on ultrasound

A high-risk NIPT result for aneuploidies

A high-risk double test/triple test result for aneuploidies

Based only on the maternal age ≥ 35 years old

**Table 3.** Karyotype Results
Disease form	n	%
Pure trisomy 13	47	94%
Mosaicism	1	2%
Translocation	2	4%
Total	50	100%

Table 3. Karyotype Results

Disease form

Pure trisomy 13

94%

Mosaicism

Translocation

Total

100%

**Table 4.** Features of Ultrasound in the First Trimester
Features of ultrasound in the first trimester	Trisomy 13	Normal	P-value
NT: nuchal translucency.
Total number of fetuses examined by ultrasound in the first trimester	23	1,230
Increased NT ≥ 3 mm	18 (78.26%)	40 (3.25%)	< 0.0001
NT < 3 mm	5 (21.74%)	1,190 (96.75%)
Tricuspid valve regurgitation	1 (4.35%)	1 (0.08%)	< 0.0001

Table 4. Features of Ultrasound in the First Trimester

Features of ultrasound in the first trimester

Trisomy 13

Normal

P-value

NT: nuchal translucency.

Total number of fetuses examined by ultrasound in the first trimester

1,230

Increased NT ≥ 3 mm

18 (78.26%)

40 (3.25%)

< 0.0001

NT < 3 mm

5 (21.74%)

1,190 (96.75%)

Tricuspid valve regurgitation

1 (4.35%)

1 (0.08%)

< 0.0001

**Table 5.** Features of Ultrasound in the Second Trimester
Features of ultrasound in the second trimester	Fetuses with trisomy 13	Normal fetuses	P-value
Total number of ultrasound fetuses in the second trimester	26	23	1	2	2,936
Facial malformations	14 (53.85%)	12	0	2	10 (0.34%)	< 0.0001
Cleft lip, cleft palate	13 (50%)	11	0	2	9 (0.31%)
Absent nasal bone	1 (3.85%)	1	0	0	2 (0.07%)
Cyclopia	1 (3.85%)	1	0	0	0 (0%)
Nasal proboscis	1 (3.85%)	1	0	0	0 (0%)
Brain anomalies	7 (26.92%)	7	0	0	3 (0.10%	0.0005
Holoprosencephaly	3 (11.54%)	3	0	0	0 (0%)
Ventriculomegaly	3 (11.54%)	3	0	0	3 (0.10%
Enlarged cisterna magna	2 (7.69%)	2	0	0	0 (0%)
Heart defects	7 (26.92%)	6	1	0	13 (0.44%)	< 0.0001
Disproportionate heart	4 (15.38%)	4	0	0	5 (0.17%)
Ventricular septal defect	4 (15.38%)	3	1	0	7 (0.24%)
Ventricular outflow abnormalities	3 (11.54%)	3	0	0	4 (0.14%)
Tricuspid valve regurgitation	1 (3.85%)	1	0	0	2 (0.07%)
Abdominal wall abnormalities	6 (23.08%)	6	0	0	3 (0.10%	0.0002
Omphalocele	6 (23.08%)	6	0	0	3 (0.10%
Kidney anomalies	7 (26.92%)	6	0	1	13 (0.44%)	< 0.0001
Enlarged and echogenic kidneys	3 (11.54%)	3	0	0	2 (0.07%)
Renal pelvis dilatation	4 (15.38%)	3	0	1	11 (0.37%)

Table 5. Features of Ultrasound in the Second Trimester

Features of ultrasound in the second trimester

Fetuses with trisomy 13

Normal fetuses

P-value

Total

Pure trisomy 13

Mosaicism

Translocation

Total number of ultrasound fetuses in the second trimester

2,936

Facial malformations

14 (53.85%)

10 (0.34%)

< 0.0001

Cleft lip, cleft palate

13 (50%)

9 (0.31%)

Absent nasal bone

1 (3.85%)

2 (0.07%)

Cyclopia

1 (3.85%)

0 (0%)

Nasal proboscis

1 (3.85%)

0 (0%)

Brain anomalies

7 (26.92%)

3 (0.10%

0.0005

Holoprosencephaly

3 (11.54%)

0 (0%)

Ventriculomegaly

3 (11.54%)

3 (0.10%

Enlarged cisterna magna

2 (7.69%)

0 (0%)

Heart defects

7 (26.92%)

13 (0.44%)

< 0.0001

Disproportionate heart

4 (15.38%)

5 (0.17%)

Ventricular septal defect

4 (15.38%)

7 (0.24%)

Ventricular outflow abnormalities

3 (11.54%)

4 (0.14%)

Tricuspid valve regurgitation

1 (3.85%)

2 (0.07%)

Abdominal wall abnormalities

6 (23.08%)

3 (0.10%

0.0002

Omphalocele

6 (23.08%)

3 (0.10%

Kidney anomalies

7 (26.92%)

13 (0.44%)

< 0.0001

Enlarged and echogenic kidneys

3 (11.54%)

2 (0.07%)

Renal pelvis dilatation

4 (15.38%)

11 (0.37%)

**Table 6.** Number of Anomalies of Fetuses Detected on the Second Trimester Ultrasound
Number of anomalies	Trisomy 13	Normal	P-value
No anomaly	4 (15.38%)	2,899 (98.74%)	< 0.0001
Only one anomaly	8 (30.77%)	33 (1.12%)
2 - 3 anomalies	12 (46.15%)	4 (0.14%)
More than three anomalies	2 (7.69%)	0 (0%)
Total	26	2,936

Table 6. Number of Anomalies of Fetuses Detected on the Second Trimester Ultrasound

Number of anomalies

Trisomy 13

Normal

P-value

No anomaly

4 (15.38%)

2,899 (98.74%)

< 0.0001

Only one anomaly

8 (30.77%)

33 (1.12%)

2 - 3 anomalies

12 (46.15%)

4 (0.14%)

More than three anomalies

2 (7.69%)

0 (0%)

Total

2,936