Background: Preterm delivery is a major health problem and contributes to more than 50% of all neonatal and infant deaths. Recently, there has been a renewed interest in the use of cervical pessaries as a safe and effective intervention with few maternal side-effects for the prevention of preterm birth in both single and twin pregnancies.

Case presentation: A 43-year-old gravida 5, para 1 (previous preterm birth at 24 weeks) patient with an in vitro fertilization twin pregnancy had an Arabin cervical pessary placed at 19 weeks of pregnancy due to the presence of cervical funneling identified by ultrasound screening. She developed chorioamnionitis and sepsis and delivered at 21 3/7 weeks after extraction of the pessary.

Conclusion: Severe maternal infection may complicate pessary treatment for the prevention of preterm birth. Careful follow-up is necessary in women with a cervical pessary during pregnancy, particularly when important funneling is present.