First-trimester biomarkers and ultrasound biometries in relation to growth discordance in monochorionic diamniotic twins

Figures & data

Table 1. Maternal characteristics according to birth weight discordance in the study population (n = 762 monochorionic diamniotic twin pregnancies).

	Birth weight discordance
	<10% n = 404	10–24.9% n = 268	≥25%
			All n = 90	Umbilical cord occlusion n = 20	sFGR n = 60	Both twins under 10th percentile n = 10
Maternal age in years,
mean (SD)	31.4 (4.7)	31.1 (5.1)	31.5 (5.3)	31.7 (4.0)	31.8 (4.8)	29.6 (5.1)
≥35 years, n (%)	90 (22.3)	63 (23.5)	23 (25.6)	3 (15.0)	18 (30.0)	2 (20.0)
BMI in kg/m^2, median (IQR)	23.0 (20.0–26.0)	23.0 (20.0–26)	23.0 (20.0–26.0)	22.5 (19.0–25.0)	24 (21.0–27.0)	21 (20.0–22.0)
Missing data	6	6	5	2	2	1
Smoker, n (%)
Yes	22 (5.5)	26 (9.7)	7 (7.8)	2 (10.0)	4 (6.7)	1 (10.0)
No	380 (94.5)	239 (90.3)	83 (92.2)	18 (90.0)	56 (93.3)	9 (90.0)
Missing data	2	1
Parity, n (%)
Nulliparous	152 (42.7)	115 (47.7)	39 (47.0)	10 (53.6)	25 (45.5)	4 (44.4)
Multiparous	204 (57.3)	126 (52.3)	49 (53.0)	9 (47.4)	30 (54.5)	5 (55.6)
Missing data	48	27	7	1	5	1
Ethnicity, n (%)
Afrocaribbean	9 (2.3)	1 (0.4)	1 (1.1)	0	1 (1.7)	0
Asian	9 (2.3)	6 (2.3)	3 (3.4)	0	2 (3.3)	1 (11.1)
Caucasian	357 (90.4)	250 (94.7)	82 (93.2)	18 (100)	56 (93.3)	8 (88.9)
Oriental	6 (1.5)	3 (1.1)	1 (1.1)	0	1 (1.7)	0
Other	14 (3.5)	4 (1.5)	1 (1.1)	0	0	1
Missing data	9	1	2	2
Spontaneous conception, n (%)
Yes	346 (86.5)	217 (81.9)	74 (83.1)	16 (80.0)	48 (81.4)	10 (100.0)
No	54 (13.5)	48 (18.1)	15 (16.9)	4 (20.0)	11 (18.6)	0
Missing data	4	3	1		1

sFGR: selective fetal growth restriction; SD: standard deviation; IQR: interquartile range

Figure 1. ROC curve for BWD ≥25% according to CRL discordance (Panel A) and NT discordance (Panel B). BWD: birth weight discordance; CRL: crown-rump length; NT: nuchal translucency.