Clinical Profile and Risk Factors of Group B Streptococcal Colonization in Mothers from the Eastern District of China

Table 1

Demographic data and associations between risk factors and GBS colonization in pregnant women with gestation of >34 weeks.

Variables	n	Maternal GBS colonization		value	OR (95% CI)
		Positive, n (%)	Negative, n (%)
Maternal age (years)
18–29	1300	81 (6.2)	1219 (93.8)	Ref	Ref
30–45	1461	104 (7.1)	1357 (92.9)	0.001	1.009 (0.990, 1.030)
Hb
<110 g/L	781	45 (5.8)	736 (94.2)	Ref	Ref
≥110 g/L	1980	140 (7.1)	1840 (92.9)	0.099	1.014 (0.993, 1.036)
Prelabor rupture of membrane
No	2291	146 (6.4)	2145 (93.6)	Ref	Ref
Yes	470	39 (8.3)	431 (91.7)	0.018	1.021 (0.992, 1.051)
Premature delivery
No	2727	181 (6.6)	2546 (93.4)	Ref	Ref
Yes	34	4 (11.8)	30 (88.2)	0.235	1.058 (0.936, 1.197)
Gestational age at birth
Below average gestational age	1205	110 (9.1)	1095 (90.9)	Ref	Ref
Above average gestational age	1556	75 (4.8)	1481 (95.2)	0.001	0.955 (0.935, 0.975)
Delivery method
Vaginal	1986	125 (6.3)	1861 (93.7)	Ref	Ref
Cesarean section	775	60 (7.7)	715 (92.3)	0.072	1.016 (0.992, 1.040)
Birth weight
Below average birth weight	1380	89 (6.4)	1291 (93.6)	Ref	Ref
Above average birth weight	1381	96 (7)	1285 (93)	0.598	1.005 (0.985, 1.026)
Fetal sex
Boy	1413	94 (6.7)	1319 (93.3)	Ref	Ref
Girl	1363	95 (7.0)	1268 (93.0)	0.075	1.000 (0.981, 1.021)
Gravidity
1	1308	88 (6.7)	1220 (93.3)	Ref	Ref
2	851	59 (6.9)	792 (93.1)	0.853	1.002 (0.979, 1.026)
3	380	26 (6.8)	354 (93.2)	0.938	1.001 (0.971, 1.033)
4	151	7 (4.6)	144 (95.4)	0.324	1.008 (0.942, 1.016)
5	53	4 (7.5)	49 (92.5)	0.816	1.009 (0.933, 1.091)
6	14	0 (0)	14 (100)	0.315	1.033 (0.919, 1.146)
7	4	1 (25)	3 (75)	0.147	1.244 (0.706, 2.190)
Parity
Primiparous	1829	127 (6.9)	1702 (93.1)	Ref	Ref
2^nd parity	889	56 (6.3)	833 (93.7)	0.529	0.993 (0.972, 1.014)
3^rd parity	42	2 (4.8)	40 (95.2)	0.581	0.977 (0.912, 1.047)
4^th parity	1	0 (0)	1 (100)	0.785	0.931 (0.919, 0.942)
Gestational age for GBS screening
<35 weeks	79	7 (8.9)	72 (91.1)	Ref	Ref
35–36 weeks	825	56 (6.9)	759 (93.1)	0.509	0.979 (0.911, 1.051)
36–37 weeks	1171	71 (6)	1104 (94)	0.315	0.970 (0.904, 1.041)
37–38 weeks	451	33 (7.3)	421 (92.7)	0.620	0.983 (0.913, 1.058)
>38 weeks	235	18 (7.6)	220 (92.4)	0.711	0.986 (0.912, 1.066)