First Trimester Aneuploidy Screening Program for Preeclampsia Prediction in a Portuguese Obstetric Population

Table 1

Demographic characteristics of the study population.

Variable	Unaffected pregnancy (𝑛=4659)	PE (𝑛=140)	EO-PE (𝑛=35)	LO-PE (𝑛=105)
Maternal age, years, median (IQR)^*a	29.9 (25.8–33.0)	31.0 (27.7–33.6)	30.0 (25.0–34.9)	31.0 (28.0–33.0)
Maternal weight, median (IQR)
Kg^*a	63.5 (57.0–72.0)	70.0 (60.9–82)	73.0 (64.5–82.0)	69.3 (60.6–83.4)
MoM^*a	0.99 (0.89–1.13)	1.10 (0.95–1.28)	1.14 (1.01–1.28)	1.07 (0.94–1.30)
Ethnicity, 𝑛 (%)
White	4529 (97.2)	138 (98.6)	34 (97.1)	104 (99.0)
Black	82 (1.8)	1 (0.7)	1 (2.9)	0 (0.0)
Other	48 (1.0)	1 (0.7)	0 (0.0)	1 (1.0)
Nulliparous, 𝑛 (%)^b	2843 (61.0)	98 (70.0)	27 (77.1)	71 (67.6)
Medical history, 𝑛 (%)
Chronic hypertension^b	104 (2.2)	12 (8.6)	5 (14.3)	7 (6.7)
Renal disease	5 (0.1)	1 (0.7)	1 (2.9)	0 (0.0)
Diabetes mellitus^b	47 (1.0)	9 (6.4)	1 (2.9)	8 (7.6)
Smoking during pregnancy, 𝑛 (%)	975 (20.9)	21 (15.0)	6 (17.1)	15 (14.3)
Spontaneous conception, 𝑛 (%)	4486 (96.3)	130 (92.9)	33 (94.3)	97 (92.4)
Ultrasound markers, median (IQR)
CRL, mm	62.9 (56–70)	64.5 (58–70)	63.2 (56–68.9)	65.0 (59–70.5)
NT, mm	1.5 (1.2–1.8)	1.5 (1.2–1.8)	1.5 (1.2–1.9)	1.5 (1.1–1.8)
Maternal serum, median (IQR)
PAPP-A, MoM^*a	1.01 (0.63–1.60)	0.85 (0.56–1.35)	0.93 (0.33–1.39)	0.85 (0.58–1.33)
Free 𝛽-hCG, MoM	1.00 (0.66–1.54)	1.10 (0.66–1.64)	0.93 (0.53–1.38)	1.17 (0.70–1.76)
Obstetric outcomes
Gestational hypertension, 𝑛 (%)	57 (1.2)	0 (0.0)	0 (0.0)	0 (0.0)
Cesarean section, 𝑛 (%)^b	1589 (34.1)	98 (70.5)	31 (88.6)	67 (64.4)
Gestational age at delivery, weeks, median (IQR)^*a	39 (38–40)	37 (35–38)	34 (29–36)	37 (36–39)
Neonatal outcomes
Male, 𝑛 (%)	2367 (50.8)	67 (48.2)	19 (54.3)	48 (46.2)
Stillbirth, 𝑛 (%)	14 (0.3)	2 (1.4)	2 (5.7)	0 (0.0)
Birth weight, g, median (IQR)^*a	3165 (2873–3440)	2670 (2150–3055)	1910 (1050–2440)	2830 (2481–3158)
LBW, 𝑛 (%)^b	354 (7.6)	55 (39.6)	27 (77.1)	28 (26.9)

PE: preeclampsia; EO-PE: early-onset preeclampsia; LO-PE: late-onset preeclampsia; IQR: interquartile range; CRL: crown-rump length; NT: nuchal translucency thickness; 𝛽-hCG: beta-subunit of human chorionic gonadotropin; PAPP-A: pregnancy-associated plasma protein-A; MoM: multiple of the median; LBW: low birth weight. Significant comparisons between unaffected pregnancies and preeclampsia cases (𝑃<0.05) using: *Mann-Whitney 𝑈 test, ^aKruskal-Wallis test, and ^bPearson 𝜒².