. 2021 Oct 28;12:753551. doi: 10.3389/fpsyg.2021.753551

TABLE 2.

Birth risks and clinical outcomes and group comparisons.

Birth factors and clinical outcomes			Preterm groups
			Extremely	Very	Moderate/late	p
Prenatal care visits		MD (P25 – P75)	4 (3–4)^a	5 (4–7)^b	7 (4–8)^b	0.001
Preeclampsia		N (%) – Yes	15 (33.3)	31 (32)	18 (58.1)^*	0.027
Twin pregnancy		N (%) – Yes	9 (20.0)	29 (28.7)	5 (13.9)	0.160
Birth delivery	Cesarean	N (%)	34 (75.6)	67 (69.1)	25 (73.5)	0.700
	Vaginal		11 (24.4)	30 (30.9)	9 (26.5)
Sex	Boys	N (%)	23 (50)	59 (57.8)	18 (47.4)	0.456
	Girls	N (%	23 (50)	43 (42.2)	20 (52.6)
Gestational age (weeks)		M (SD)	26.5 (1.1)^a	30.1 (1.3)^b	33.4 (1.4)^c	<0.001
Length at birth (cm)		M (SD)	33.7 (3.2)^a	38.9 (3.2)^b	41.0 (3.6)^c	<0.001
Cephalic perimeter at birth (cm)		M (SD)	24 (2.0)^a	27.4 (2.2)^b	29.5 (1.8)^c	<0.001
Weight at birth (grams)		M (SD)	838 (195)^a	1333 (328)^b	1717 (622)^c	<0.001
Weight (grams)	500–1000 g	N (%)	36 (80)^*	13 (13.3)	–	<0.001
	1000–1500 g		9 (20)	67 (68.4)^*	21 (67.7)
	1500–2000 g		–	18 (18.4)	10 (32.3)^*
Apgar 5th min		MD (P25 – P75)	7 (6–8)^a	8 (8–9)^b	8 (7–9)^ab	0.001
NICU stay (days)		MD (P25 – P75)	99 (77–116)^c	49 (36–69)^b	30 (26–38)^a	<0.001
Invasive mechanical ventilation (days)		MD (P25 – P75)	6 (0–26)^b	0 (0–2)^a	0 (0–0)^a	< 0.001
Oxygen therapy (days)		MD (P25 – P75)	5 (0–25)^b	0 (0–7)^a	0.5 (0–5)^a	0.014
Periventricular hemorrhage		N (%) – Yes	20 (45.5)	24 (25.3)	10 (37.0)	0.053
Leukomalacia		N (%) – Yes	4 (9.3)	4 (4.2)	3 (11.1)	0.323
NICU Seizures		N (%) – Yes	18 (39.1)^*	16 (16.3)	6 (18.8)	0.008

MD, median; M, mean; SD, standard deviation.

^a,b,cDifferent letters: significant differences at Tukey (symmetric distribution) or Dunn (asymmetric distribution), p < 0.050 (quantitative variables).

*Statistically significant association by the residual test adjusted to 5% significance, p < 0.050 (categorical variables).