Syphilis-attributable adverse pregnancy outcomes in China: a retrospective cohort analysis of 1187 pregnant women with different syphilis treatment

Table 3 Risk of composite adverse outcomes among syphilis-seropositive pregnant women by syphilis treatment status in Guangzhou, China, 2014–2016^a

Treatment during pregnancy	Women with adverse outcomes, N (%)	Crude RR (95% CI)	Adjusted RR (95% CI)
Treatment initiation
Penicillin <28w	109 (16)	reference	reference
Penicillin ≥28w	35 (17.5)	1.10 (0.77–1.55)	1.13 (0.79–1.61) ^b
No treatment	97 (33.8)	2.11 (1.67–2.68)	2.07 (1.59–2.68) ^b
Treatment course
2 courses	73 (14.2)	reference	reference
1 course	38 (17.8)	1.26 (0.88–1.80)	1.36 (0.94–1.96)^c
Insufficient treatment	33 (21.3)	1.50 (1.04–2.17)	1.58 (1.08–2.31)^c
No treatment	97 (33.8)	2.38 (1.82–3.11)	–

Abbreviations: RR relative risk, CI confidence intervals
^aNone-penicillin treatment cases were excluded
^bAdjusted for age, marital status, household registration, and multipara status
^c Adjusted for age, marital status, household registration, multipara status, and the start time of treatment in the gestation