Risk of adverse pregnancy outcome in isolated single umbilical artery diagnosed at the mid-trimester anomaly scan: a large Danish retrospective cohort study

Figures & data

Table 1. Baseline maternal- and pregnancy related characteristics.

	Reference (n = 115,726)	Isolated SUA (n = 775)	p-value
Maternal age (mean (SD))*	30.9 (4.74)	31.4 (4.74)	0.004
BMI (median (IQR 25–75))	22.5 (20.6–25.2)	22.9 (20.7–25.6)	0.017
Missing values	1590 (1.4)	4 (0.52)
Ethnicity (n (%))			0.585
Caucasian	100,418 (86.8)	683 (88.1)
Other	11,025 (9.5)	70 (9.0)
Missing values	4,283 (3.7)	22 (2.8)
Smoking (n (%))			0.171^‡
Yes	7,680 (6.6)	61 (7.9)
No	107,635 (93.0)	708 (91.4)
Stopped in 1. trimester	331 (0.29)	6 (0.77)
Missing values	80 (0.07)	0 (0.00)
Parity (n (%))			0.687^‡
0	52,359 (45.2)	361 (46.6)
1	38,001 (32.8)	255 (32.9)
≥ 2	14,572 (12.6)	108 (13.9)
Missing values	10,794 (9.3)	51 (6.6)
Conception (n (%))			<0.001^‡
Natural	105,344 (91.0)	671 (86.6)
ART	9,381 (8.1)	100 (12.9)
FER	49 (0.04)	1 (0.13)
ICSI	1,961 (1.7)	22 (2.8)
Insemination	3,816 (3.3)	34 (4.4)
IVF	3,555 (3.1)	43 (5.5)
Missing values	1,001 (0.86)	4 (0.52)
GA in days at first-trimester scan (median (IQR 25–75))*	91 (88–93)	90 (88–93)	0.133
GA in days at mid-trimester scan (median (IQR 25–75))*	139 (137–142)	139 (136–142)	0.292
GA in days at birth (median (IQR 25–75))*	281 (273–287)	280 (272–287)	0.045
Sex (n (%))*			0.003
Males	59,421 (51.5)	354 (46.2)
Females	56,015 (48.5)	413 (53.8)
Birthweight in grams (median (IQR 25–75))	3,500 (3180–3825)	3,380 (3020–3710)	<0.001
Missing values	764 (0.66)	12 (1.5)

*No missing values.

^‡P-values: Smoking (Yes vs. (No + Stopped in 1. Trimester)); Parity (0 vs. 1 vs. ≥ 2); Conception (Natural vs. ART).

Abbreviations: SD, Standard deviation; IQR, Interquartile range; ART, Artificial reproductive technology; FER/FET, Frozen embryo replacement/transfer; ICSI, Intracytoplasmic Sperm Injection; IVF, in vitro fertilization; GA, Gestational age.

Table 2. Congenital malformations recognized after the mid-trimester malformation scan in 33 cases with unrecognized malformations.

Malformation (ICD-10)	Total cases n(%)	Frequency	Identified
CNS	1 (3.03)
Microcephaly (Q02.9)		1	Postnatal
Tethered cord (Q06.8)*		2	Postnatal
Cardiovascular	12 (36.4)
Atrial septal defect, l.g. (Q21.1)		4	Postnatal (3) Detected in autopsy (1)
Ventricular septal defect, Perimembranous, l.g. (2) (Q21.0) Ventricular septal defect, Perimembranous, m.g. (2) (Q21.0)		4	Postnatal (2) Postnatal, operated 3 months old (2)
Ventricular septal defect, Muscular, l.g. (Q21.0)		3	Postnatal (1) Expert scan after 2nd trimester scan (1) Detected in autopsy (1)
Persistent foramen ovale, l.g. (Q21.1)*		3	Postnatal
Congenital pulmonary valve stenosis, l.g. (Q22.1)		1	Postnatal
Congenital stenosis of aortic valve, m.g. (Q23.0)		1	Postnatal, operated 11 months old
Congenital mitral stenosis, l.g. (Q23.2)		1	Postnatal
Congenital mitral insufficiency, l.g. (Q23.3)		1	Postnatal, operated 5 years old
Stenosis ductus arteriosus (Q24.9)		1	Detected in autopsy
Patent ductus arteriosus, l.g. (1) (Q25.0)* Patent ductus arteriosus, m.g. (1) (Q25.0)*		2	Postnatal
Coarctation of aorta, l.g. (Q25.1)		1	Postnatal
Other congenital malformations of pulmonary artery and anomalous origin of subclavian artery, m.g. (Q25.7/Q25.48)		1	Postnatal, operated due to compressed trachea (pulmonary sling) 11 months
Arteria lusoria (Q25.48)		1	Detected in autopsy
Persistent left superior vena cava to left atrium (Q26.1)		1	Detected in autopsy
Gastrointestinal	8 (24.2)
Atresia of esophagus with tracheoesophageal fistula (Q39.1)		3	Postnatal (1) Detected in autopsy (1) Growth scan in third trimester (1)
Congenital hypertrophic pyloric stenosis (Q40.0)		1	Postnatal
Congenital absence, atresia and stenosis of duodenum (Q41.0)		1	Growth scan in third trimester
Congenital absence, atresia and stenosis of anus with/without fistula (Q42.3/Q42.2)		6	Postnatal
Inguinal hernia (Q40.9)*		1	Postnatal
Genitourinary	13 (39.4)
Undescended testicle (Q53.1/Q53.9)*		11	Postnatal
Hypospadias (Q54.1/ Q54.2/Q54.9)		8	Postnatal
Congenital adhesions of scrotum and penis (Q55.5)*		1	Postnatal
Renal agenesis, unilateral (Q60.0)		2	Postnatal (1) Expert scan after mid-trimester scan (1)
Lobulated, fused and horseshoe kidney (Q63.1)		3	Postnatal (2) Expert scan after mid-trimester scan (1)
Renal malrotation (Q63.2)		1	Postnatal
Musculoskeletal	3 (9.1)
Congenital stenosis and stricture of lacrimal duct (Q10.5)*		1	Postnatal
Accessory auricle (Q17.0)*		1	Postnatal
Choanal atresia (Q30.0)		1	Postnatal
Cleft soft palate (Q35.3)*		1	Postnatal
Micrognathia (Q38.5)		2	Postnatal
Talipes calcaneovalgus or calcaneo valgus (Q66.3/Q66.8/Q66.4)*		3	Postnatal (2) Expert scan after mid-trimester scan (1)
Congenital deformity of sternocleidomastoid muscle (Q68.0)*		2	Postnatal
Polydactyly (Q69.0/Q69.1/Q69.2/Q69.9/Q74.8)*		4	Postnatal
Syndactyly (Q70.9)*		1	Postnatal
Craniosynostosis (Q75.0)*		1	Postnatal
Other congenital malformations of ribs (Q76.6)*		1	Postnatal
Other	0 (0.00)
Other congenital malformations of iris (Q13.2)*		1	Postnatal
Aures alatae (Q17.5)*		1	Postnatal
Fonastenia (Q18.2)*		1	Postnatal
Ankyloglossia (Q38.1)*		4	Postnatal
Congenital dislocation of hip (Q65.2/Q65.6)*		2	Postnatal
Plagiocephaly (Q67.3)*		4	Postnatal

Note: Each case can have multiple malformations affecting one or several organ systems.

*Irrelevant minor malformations excluded from total cases and analyses.