(1284) Factors associated with pro-inflammatory cervicovaginal cytokine milieu among gravidas with an asymptomatic short mid-trimester cervix

Sociodemographic factors are linked to PTB, but underlying mechanisms are unclear. Inflammation is a key pathway implicated in PTB; it may be detected sub-clinically in pregnancy. In a prior analysis of the multicenter TOPS RCT of pessary vs. usual care in singletons with a mid-trimester short CL (≤20 mm) and no prior PTB, we derived a composite pro-inflammatory cytokine score from 12 cervicovaginal fluid (CVF) cytokines obtained at randomization. Higher scores were associated with PTB and maternal and neonatal infections. Herein, we sought to identify factors associated with CVF inflammation in mid-pregnancy.


Study Design:

Secondary analysis of the TOPS RCT; participants with a CVF cytokine score were included. The primary outcome was cytokine category - high (≥75^th centile), average (≥25^th but < 75^th centile), or low (< 25th centile). The secondary outcome was cytokine score as an ordinal variable. We evaluated the association between demographic and clinical factors present before or at CVF collection and cytokine score category.


Results:

Of 544 RCT participants, 531 met inclusion criteria: 105 (20%) had low, 305 (57%) average, and 121 (23%) high cytokine scores. Clinical parameters at randomization, including cervical length, presence of intra-amniotic debris and funneling, and ability to visualize membranes on exam did not vary by cytokine score, nor did reports of vaginal discharge or recent intercourse (Table 1). However, high levels of CVF inflammation were associated with younger age, less education, higher pre-pregnancy BMI, being single / not living with a partner, receipt of antifungal(s), smoking during pregnancy (Table 1), and vaginal dysbiosis at randomization (Figure 1). These associations were similar when considering the cytokine score ordinally (data not shown).


Conclusion:

Sociodemographic characteristics have long been recognized as PTB risk factors and are associated with mid-pregnancy CVF inflammation among asymptomatic gravidas with a short cervical length. These findings suggest that sub-clinical inflammation may be a key mechanism linking social disadvantage to PTB risk.