To describe clinical characteristics, and perinatal outcomes of patients with a short cervix, in which intra-amniotic inflammation using AF Interleukin-6 (IL-6) concentration was measured. Series of cases including pregnant patients between 17–32 weeks of gestation with a short cervix in our institution between January 2018 and April 2021. A total of 37 patients with a short cervix were identified, AF concentrations of IL-6 were measured in nine patients. Retrieved data included maternal and perinatal outcomes, amniocentesis results and inflammatory markers such as Interleukin-6. Descriptive measures are reported according to their distribution. In patients in which AF concentration of IL-6 was measured and intra-amniotic inflammation was diagnosed (AF IL-6 > 2.6 ng/mL) (n = 4), a combination of antibiotics including ceftriaxone, metronidazole and clarithromycin was started in 3 of them. Patients with intra-amniotic inflammation treated with AB have better outcomes than patients in which IAI was not diagnosed. The gestational age at delivery was longer, with less preterm deliveries and better outcomes. In patients with a short cervix, the use of Interleukin-6 can identify patients with intra-amniotic inflammation, which are at a greater risk of adverse outcomes including shorter interval-to-delivery and worst perinatal outcomes. VP46.18: Table 1. Perinatal outcomes in patients with a short cervix and intra-amniotic inflammation in a centre from Colombia