Both Acute and Chronic Placental Inflammation Are Overrepresented in Term Stillbirths: A Case-Control Study

Table 1

(a) Maternal and child demographic data from stillborns and liveborn controls.

Variable	𝑛	Stillborns	𝑛	Liveborns	𝑃 value
Gestational age in completed weeks	126	39.4±1.6	273	39.3 ± 1.2	ns
Maternal age	126	31.8±4.8	273	30.3 ± 5.3	<0.01
BMI	114	24.3 (18.2–43.7)	259	23.1 (14.9–47.1)	<0.001
Previous miscarriage	124	35 (28.2)	269	45 (16.7)	<0.01
Smoking at registration in maternity centre	122	13 (10.7)	266	17 (6.4)	ns
Smoking at 32 weeks	104	7 (6.7)	221	10 (4.5)	ns
Primipara	124	68 (54.8)	269	142 (52.8)	ns
Previous stillbirth (≥1 para)	56	2 (3.6)	127	0 (0.0)	ns*
Sever illness or pregnancy complication	126	13 (10.3)	273	26 (9.5)	ns
Hb at registration in maternity centre	122	129.0±11.6	262	127.5 ± 11.1	ns
Induction of labour	126	70 (55.6)	273	37 (13.6)	<0.001
Caesarean section	126	10 (7.9)	273	26 (9.5)	ns
Sex of the infant (male/female)	126	60/66 (47.6/52.4)	273	153/120 (56.0/44.0)	ns
Birth weight	126	3243±585	273	3560 ± 509	<0.001
Small for gestational age	126	27 (21.4)	273	8 (2.9)	<0.001

BMI: body mass index; Hb: hemoglobin concentration; ns: not significant
BMI was not related to age in linear logistic regression
Data are presented as mean ± SD, median (min-max) or 𝑛 (%); Student’s 𝑡-test, Mann-Whitney U-test, Chi-squared test, or Fisher’s exact test*.

(b) Histopathological findings in placentas from stillborns and liveborn controls.

Variable	𝑛	Stillborns	𝑛	Liveborns	𝑃 value
Placental weight	126	431.0 ± 107.9	269	483.1 ± 97.7	<0.001
Low placental weight versus gestational age	126	64 (50.8)	269	90 (33.5)	<0.001
Immature placental villi	126	18 (14.3)	273	7 (2.6)	<0.001
Infarction	126	50 (39.7)	273	80 (29.3)	<0.05
Intervillous thrombosis	126	43 (34.1)	273	71 (26.0)	ns
Fetal thrombosis	126	80 (63.5)	272	44 (16.2)	<0.001
Chorioamnionitis	126	82 (65.1)	273	111 (40.7)	<0.001
Chorioamnionitis grade 1		40 (31.7)		80 (29.3)
Chorioamnionitis grade 2-3		42 (33.3)		31 (11.4)
Vasculitis and/or funisitis	126	37 (29.4)	272	43 (15.8)	<0.01
Villitis	126	23 (18.3)	273	14 (5.1)	<0.001
Villitis <1%		8 (6.4)		5 (1.8)
Villitis ≥1%		15 (11.9)		9 (3.3)

Data are presented as mean ± SD or 𝑛 (%); Student’s 𝑡-test, Chi-squared test.