The patient with asymptomatic shortened cervix at 23 to 28 weeks: is delivery imminent?

We investigated whether the presence of symptoms predicts the timing of subsequent spontaneous preterm birth in a cohort of women with cervical length (CL) <1.5 cm. A retrospective cohort study was conducted that included patients from 23 to 28 weeks' gestation with a CL <1.5 cm on routine ultrasound. Two groups were defined on the basis of presenting symptoms at the time of the ultrasound examination: asymptomatic patients and those with symptoms of preterm labor. The incidence of delivery within 2 weeks was determined for both groups. A total of 88 patients with CL <1.5 cm were identified from an ultrasound database. There were 52 patients with CL <1.5 cm and no symptoms. Of these, 1 (1.9%) delivered within 2 weeks. The remaining 36 patients had a CL <1.5 cm and symptoms of preterm labor. Of these, 11 (30.6%) delivered within 2 weeks (relative risk 15.9, 95% confidence interval 2.1 to 118). Premature cervical shortening at 23 to 28 weeks, in the absence of symptoms of preterm labor, is rarely associated with preterm delivery within 2 weeks. Following those patients clinically may prevent prolonged hospitalization and allow steroid administration closer to the date of delivery.