(168) Sub-clinical inflammatory trajectories in mid-pregnancy from vaginal and blood-derived cytokines and risk of early PTB

Primary outcome: PTB < 35 wks. Secondary outcomes: PTB < 37, < 32 wks, sample2 time-to-delivery. Cox models assessed factors associated with time-to-delivery (z-change score availability to delivery).

 

Results:

Of 293 participants, 31/267 (21%) with 2 vag had PTB < 35w, 23/134 (17%) with 2 blood had PTB < 35w, and 16/105 (15%) with 2 vag & 2 blood samples had PTB< 35w. Sample1 was collected at median 16.4 (IQR 15.7–18.6) wks; sample2 a median 5 (IQR 4–6.8) wks later. Total-z-change-vag (mean -0.46 ± 6.7) and total-z-change-blood (mean -0.87 ± 11.5) scores were similar, p=0.76. Six individual vag cytokines (IL-1β, IL-4, IL-6, IL-8, TNF-α, and GCSF), the total-z-change-vag score (composite of all 12), and the high-risk-z-change subset (composite of the 6 individual scores IL-1β, IL-4, IL-6, IL-8, TNF-α, and GCSF) all increased in hose with PTB < 35 weeks vs. later delivery, Figure 1. No blood cytokine z-changes varied by PTB status. In Cox models, cytokine change scores in vag, but not blood samples remained associated with time-to-delivery, Table.

 

Conclusion:

Increasing subclinical inflammation among asymptomatic patients in mid-pregnancy, reflected by relative increases in vaginal-derived cytokine values over time, is associated with eventual PTB. Evaluating an individual’s inflammatory trajectory may provide novel insights into PTB risk and delivery timing.