Purpose: To integrate cervical length measurement into antenatal screening and apply emergency cerclage when indicated to prevent spontaneous deliveries at < 34 weeks of gestation. Methods: Cervical length measurements of 400 pregnant volunteers were obtained at gestational weeks 12-14, 18-20 and 28-32. Whenever a cervical measurement < 30 mm was observed, vaginal cultures and bacterial vaginosis were investigated, and weekly cervical length measurements were performed thereafter. Emergency cerclage was performed whenever complete cervical effacement and >= 3 cm cervical dilatation were observed before 32 completed weeks of gestation. We adopted and tested a strategy of only emergency cerclage application when clinically indicated after ultrasound screening and microbial monitoring of short cervices. Patients were given cyclooxygenase-inhibitors, progesterone, and antibiotics in the postoperative period. Results: Spontaneous preterm births at < 34 weeks of gestation occurred in 15 women (3.8%). We performed five emergency cerclages according to the presented screening strategy between 20-28 weeks of gestation all of which reached > 34 weeks. We successfully postponed 62.5% (5/8) of deliveries before 32 completed weeks and 33.3% (5/15) of deliveries before 34 completed weeks. Conclusion: Routine cervical length measurement combined with serial transvaginal sonograms and vaginal microbial monitoring of the short cervices will avoid unnecessary prophylactic cerclages while increasing the success of emergency cerclages performed upon solid clinical findings.