Soluble ST2, a modulator of the inflammatory response, in preterm and term labor

Figures & data

Table 1. Demographic and clinical characteristics of the preterm labor sub-groups.

	Women with PTL who delivered at term (n = 49)	Women with PTL who delivered preterm without IAI (n = 21)	Women with PTL who delivered preterm with IAI (n = 31)	p
Age (years)	21 (18–29.5)	21 (17.5–27.5)	24 (18–31)	0.43
BMI (kg/m^2)	22.2 (19.6–25.5)	22.6 (20.4–27.1)	23.3 (20.8–25.2)	0.38
GA at amniocentesis (weeks)	31.2 (27.5–33.2)	33.0 (30.9–33.5)	30.4 (26.4–33.2)	0.08
IL-6 (ng/mL)	0.43 (0.27–0.68)	0.53 (0.31–0.99)	21.5 (5.9–136)	<0.0001*
WBC (cells/µL)	2 (0–5.5)	4 (0–5.0)	6 (0–190)	0.03*
Glucose (mg/dL)	32 (23.3–43.5)	28.5 (20.3–38.8)	15 (3.0–34)	0.003*
Interval to delivery (days)	53.9 (37.8–72.1)	11.9 (3.2–28)	2.1 (0–6.3)	<0.0001*
GA at delivery (weeks)	39.0 (38.1–39.6)	34.4 (33.6–35.7)	31.6 (26.4–33.6)	<0.0001*
Birth weight (grams)	3320 (2985–3560)	2470 (2030–2770)	1950 (860–2360)	<0.0001*

Values expressed as median (inter-quartile range).

PTL: preterm labor; IAI: intra-amniotic infection/inflammation; BMI: body mass index; GA: gestational age; WBC: white blood cells. *p < 0.05.

Table 2. Demographic and clinical characteristics of the women at term sub-groups.

	Term not in labor (n = 13)	Term in labor (n = 43)	p
Age (years)	29 (21–32)	22 (20–28)	0.14
GA at amniocentesis (weeks)	39.5 (39–40.5)	39 (38–40)	0.4
GA at delivery (weeks)	39.5 (39–40.5)	39 (38–40)	0.4
Birth weight (grams)	3260 (3125–3790)	3250 (3100–3700)	0.6

Values expressed as median (inter-quartile range).

GA, gestational age. *p < 0.05.

Figure 1. Amniotic fluid concentrations of sST2 in preterm labor sub-groups. The median amniotic fluid concentration of sST2 was significantly lower in women with PTL with intra-amniotic infection/inflammation (IAI) than in those who delivered preterm without IAI (median 410 ng/mL; IQR 152-699 versus median 825 ng/mL; IQR 493-1216 [p = 0.0003]) and those with PTL who delivered at term (median 410 ng/mL; IQR 152-699 versus median 673 ng/mL; IQR 468-1045 [p = 0.0003]). In the absence of IAI, there was no significant difference in the median amniotic fluid concentration of sST2 between women with PTL who delivered at term and those who delivered preterm without IAI (p = 0.4).

Figure 2. Amniotic fluid concentrations of sST2 in women at term The median amniotic fluid concentration of sST2 was similar between women at term not in labor and those at term in labor (median 341 ng/mL; IQR 260–539 ng/mL versus median 353 ng/mL; IQR 181–527 ng/mL; p = 0.9).

Figure 3. ST2 mRNA expression by the chorioamniotic membranes. The mean ST2 mRNA expression by the chorioamniotic membranes of patients who delivered preterm with acute histologic chorioamnionitis was 4-fold lower than those without this lesion (p = 0.008). −ΔCt: fold change between groups estimated by a generalized linear model.