Preterm delivery (PD) is the most important cause of neonatal mortality, particularly before the 32(nd) week of pregnancy. A short cervix is the most important quantitative marker for predicting PD. However, there are other qualitative markers such as cervical gland area, cervical funneling, and sludge. We present the case of a pregnant woman who was diagnosed with a short cervix at 14-weeks and demonstrate the use of triple therapy, which helped to achieve a good perinatal result. A 37-year-old pregnant woman (G3P0) was referred to our service at 14-weeks of pregnancy presenting with a short cervix (20 mm) and a positive sludge sign. She was hospitalized; a pessary was inserted, and started on antibiotic therapy (clindamycin and cefalotin for 10 days). At 20 weeks, she was again admitted to the hospital, and this time presented with a further shortened cervix (9 mm), cervical funneling, and a positive sludge sign, with the pessary in position. The following procedures were performed: Amniocentesis on the sludge (negative bacterioscopy), another cycle of antibiotics, administration of oral progesterone, and imaging to determine retention of pessary position. The patient was placed in the Trendelenburg position and remained hospitalized for 82 days. At 32 + 1 weeks, the fetus presented distress (tachycardia). C-section was performed, producing a live female newborn weighing 2,180 g and presenting Apgar indexes of 8/8. This case report demonstrates the importance of magnetic resonance imaging to assess the position of pessary in a pregnant woman with short cervix.