Cohort-specific effects of time were observed, where levels at 20 weeks’ gestation were found to be significantly decreased for IL-8 (–0.23 ± 0.07 pg/mL, P = 0.001) and Trp (–460.22 ± 1477.57 ng/mL, P = 0.008) compared with 15 weeks’ gestation in healthy and IBS participants, respectively. Here, CXCL8 is linked to irritable bowel syndrome.