BioMed Research International

Research Article

The Effect of Different Treatment Regimens and Multiple Risk Factors on Adverse Pregnancy Outcomes among Syphilis-Seropositive Women in Guangzhou: A Retrospective Cohort Study

Table 4

Risk factors associated with different adverse pregnancy outcomes in women with syphilis (multivariate analysis) (odds ratio and its 95% confidence interval).


Characteristic	At least one APO	Ectopic pregnancy	Spontaneous abortion^#	Stillbirth	Preterm/LBW	SGA	CS

Maternal age	0.99 (0.98-1.00)	1.08 (1.03-1.14)	1.01 (0.98-1.05)	0.96 (0.93-0.99)	1.00 (0.98-1.02)	0.98 (0.96-1.00)	0.93 (0.85-1.01)
Marital status (ref = married)	1.32 (1.03-1.69)	4.90 (2.50-9.61)	1.87 (1.14-3.07)	0.85 (0.48-1.48)	1.22 (0.86-1.72)	0.81 (0.56-1.19)	0.96 (0.27-3.33)
Educational attainment (ref = bachelor or above)
High school	1.16 (0.87-1.55)	1.09 (0.37-3.23)	1.86 (0.92-3.73)	1.44 (0.72-2.86)	1.02 (0.68-1.53)	0.93 (0.61-1.42)	0.35 (0.09-1.30)
Middle school	1.06 (0.81-1.39)	0.85 (0.30-2.38)	1.06 (0.53-2.10)	1.04 (0.53-2.03)	0.99 (0.68-1.44)	1.16 (0.79-1.70)	0.23 (0.06-0.83)
Primary school or below	1.25 (0.89-1.76)	1.51 (0.50-4.54)	0.56 (0.23-1.35)	1.34 (0.61-2.96)	1.17 (0.73-1.87)	1.42 (0.88-2.31)	0.58 (0.14-2.41)
History of syphilis infections (ref = no)	1.12 (0.94-1.34)	1.13 (0.61-2.09)	1.18 (0.78-1.77)	0.95 (0.63-1.43)	1.29 (1.01-1.66)	0.84 (0.65-1.09)	2.32 (0.89-6.03)
Partner’s current syphilis status (ref = negative)
Positive	1.08 (0.76-1.54)	1.54 (0.44-5.41)	0.87 (0.37-2.04)	0.65 (0.24-1.74)	1.20 (0.72-2.01)	0.99 (0.61-1.63)	0.66 (0.06-7.22)
Unknown	1.22 (0.99-1.49)	1.04 (0.46-2.32)	0.90 (0.56-1.46)	1.15 (0.72-1.83)	1.51 (1.12-2.05)	0.92 (0.70-1.22)	1.84 (0.50-6.82)
Syphilis treatment during pregnancy (ref = WHO-recommended treatment)
China-recommended treatment	0.47 (0.38-0.57)	0.03 (0.04-0.21)	0.11 (0.05-0.21)	0.40 (0.26-0.63)	0.52 (0.40-0.69)	0.91 (0.69-1.21)	0.49 (0.15-1.62)
Alternatives to penicillin treatment	0.63 (0.37-1.06)	—	—	0.43 (0.10-1.81)	0.84 (0.43-1.62)	1.16 (0.59-2.30)	1.77 (0.20-16.06)
No treatment	1.58 (1.25-2.00)	3.59 (1.96-6.57)	3.46 (2.30-5.20)	1.18 (0.74-1.90)	0.97 (0.69-1.38)	0.84 (0.55-1.27)	1.59 (0.52-4.88)
Log₂ titers of TRUST before treatment	1.14 (1.10-1.19)	0.89 (0.78-1.02)	1.08 (1.00-1.16)	1.05 (0.97-1.14)	1.19 (1.13-1.25)	1.10 (1.04-1.16)	1.34 (1.16-1.58)
Mode of delivery (ref = spontaneous labor)
Elective Caesarean section	—	—	—	—	0.62 (0.44-0.87)	0.65 (0.47-0.91)	2.34 (0.72-7.58)
Emergency Caesarean section	—	—	—	—	1.82 (1.38-2.40)	1.29 (0.95-1.74)	1.21 (0.38-3.83)
Gestational age at delivery in weeks	—	—	—	—	—	—	0.97 (0.78-1.20)
Birth weight in grams	—	—	—	—	—	—	1.00 (1.00-1.00)
Newborn’s sex (ref = girl)	—	—	—	—	0.85 (0.67-1.07)	—	0.90 (0.36-2.28)

APO: adverse pregnancy outcome; LBW: low birth weight; SGA: small for gestational age; CS: congenital syphilis; TRUST: toluidine red unheated serum test. The sample size for alternatives to penicillin treatment was one. ^#The sample size for alternatives to penicillin treatment was zero.