EP17.20: Amniocentesis and therapeutic amnioreduction prior to “Rescue Cerclage” (AARC Protocol)

To determine whether amniotic fluid tests would identify patients who would benefit from rescue cerclage. This was a prospective observational study conducted between December 2021-2023. We included pregnancies involving singleton and twins, gestational age (GA) between 14-24 weeks, cervical dilation <4cm, with membranes at or beyond the external os and no labour signs. Risk of intra-amniotic inflammation or infection (IAI) was assessed using amniotic fluid white cell count, interleukin-6, glucose, gram-stain and culture. Amniocentesis to delivery interval (ADI) was the primary outcome. Secondary outcomes included GA at delivery and perinatal survival. A total of 26 patients were included, with five undelivered at abstract submission. The mean amniocentesis GA was 20.9 weeks. Nine patients (42.8%) had low-risk amniocentesis results, all of whom had rescue cerclage. The mean ADI among those with low-risk amniotic fluid tests was 78.8 days with mean GA at delivery of 32.8 weeks. Among this group, perinatal survival was 100%. Twelve patients (57.2%) had high-risk amniocentesis results, of which three patients had rescue cerclage. The mean ADI among those with high-risk amniotic fluid tests was 18.1 days with mean GA at delivery of 23.0 weeks. Among this group, perinatal survival was 41.7%. There were no survivors among those who underwent rescue cerclage, whose mean ADI was 22.7 days. Our AARC protocol identifies low-risk patients for IAI who would benefit from rescue cerclage.